Toilet Fill Valve by Model: Fluidmaster 400H and 400A, Korky QuietFILL 528, and What Kohler, American Standard, TOTO and Glacier Bay Tanks Take
Match a fill valve to the overflow tube, not the brand: Fluidmaster 400H adjusts 9 to 14 inches, Korky 528MP 8-1/2 to 14, water 1/2 inch below the overflow top.
- Verified
- Updated
- 7 min read
- 11 sources
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Short answer
A toilet fill valve is matched to the overflow tube, not to the toilet brand. Fluidmaster’s 400H PerforMAX adjusts from 9 to 14 inches, and its product page names Kohler, American Standard, TOTO and Glacier Bay among the toilets it fits, on both 2 inch and 3 inch flush valves. Korky’s QuietFILL Platinum 528MP adjusts from 8-1/2 to 14 inches, and its page says it fits 99% of toilets. Both makers set the valve the same way: Fluidmaster’s 400H and 400A guides put the top of the fill valve cap roughly 3 inches above the top of the overflow pipe, and Fluidmaster and Korky both put the finished water level 1/2 inch below the top of the overflow tube, with the refill tube clipped to its rim. TOTO’s own parts store lists one Universal Fill Valve Assembly, TSU99A.XR, for both the Drake CST744S and the Carusoe CST714, two tanks that take different flappers. Measure the overflow tube first, then order.
The picks
Any 2 inch or 3 inch flush valve tank, overflow tube 9 to 14 inches
Fluidmaster 400H PerforMAX Universal Fill Valve
Fluidmaster's page: adjustable 9 to 14 inches, 1.28 to 3.5 gpf, fits Kohler, American Standard, TOTO and Glacier Bay; separate bowl water level dial
Shorter tank: adjusts down to 8-1/2 inches
Korky QuietFILL Platinum Fill Valve, 528MP
Korky's page: adjusts 8-1/2 to 14 inches, fits 99% of toilets, made for toilets since 1994 at 1.6 gpf or less; water level mark 1/2 inch below the overflow tube
Old valve had a brass shank, or you want a metal one
Fluidmaster 400A Brass Shank Universal Fill Valve
Listed on Fluidmaster's instruction index as the 400A with brass shank; the 400A guide sets the cap 3 inches above the overflow pipe and the water 1/2 inch below it
If you came here to match a fill valve to a toilet nameplate the way the flapper page does, the tape measure matters more than the brand: no maker page opened this session names a toilet that refuses a universal valve.
Which fill valve fits your toilet?
The fill valve is the tall valve on the left of the tank that refills it after a flush; the overflow tube is the open pipe in the middle that sets how high the water may rise. Every dimension below is measured from that tube.
| Toilet brand | OEM fill valve | Universal fit the maker claims | What decides it |
|---|---|---|---|
| Kohler | Not published on a Kohler page that opened this session | Fluidmaster 400H names Kohler; Korky 528MP says 99% of toilets | Overflow tube height within 9 to 14 in (400H) or 8-1/2 to 14 in (528MP) |
| American Standard | Not published on an American Standard page that opened this session | Fluidmaster 400H names American Standard; Korky 528MP says 99% of toilets | Same height check |
| TOTO Drake CST744S (3 in flapper tank) | TSU99A.XR, Universal Fill Valve Assembly, per TOTO’s parts store | Fluidmaster 400H names TOTO | Same height check |
| TOTO Carusoe CST714 (2 in flapper tank) | The same TSU99A.XR, per TOTO’s parts store | Fluidmaster 400H names TOTO | Same height check |
| Glacier Bay | Not published: Glacier Bay has no maker parts site | Fluidmaster 400H names Glacier Bay; Fluidmaster’s instruction index also lists a separate 703A valve “for Glacier Bay/Niagara” | Open the lid: if the valve matches the 703A drawing, the universal is not a like-for-like swap |
TOTO’s two listings are the useful signal. The Drake and the Carusoe take different flappers, THU500S and THU257, yet TOTO sells the same fill valve for both. The flush valve varies by tank family; the fill valve does not.
Which universal fill valves are current, and how far do they adjust?
| Valve | Adjustment range | Rated for | Where the figure is printed |
|---|---|---|---|
| Fluidmaster 400H PerforMAX | 9 to 14 in | 1.28 to 3.5 gpf, 2 in and 3 in flush valves | Fluidmaster’s 400H product page |
| Fluidmaster 400A, and the 400A brass shank | Not printed in inches on the pages that opened; the guide sets the cap 3 in above the overflow pipe | Not printed | Fluidmaster’s 400A guide and instruction index |
| Fluidmaster 400LS Leak Sentry, 400ACN 3-pack | Listed on the instruction index; ranges not opened | Not printed | Fluidmaster’s instruction index |
| Korky QuietFILL Platinum 528MP | 8-1/2 to 14 in | Toilets made since 1994, 1.6 gpf or less | Korky’s 528MP page |
| Korky QuietFILL 528 | Twist-lock adjustment, range not printed in inches | 2-piece and 1-piece toilets | Korky’s 528 page |
| Korky 2X Long Life 528X | 8-1/2 to 14 in | Toilets made since 1994, 1.6 gpf or less | Korky’s 528X page |
| Danco | Not readable: danco.com refused every request this session | Not published here | None |
Korky’s pages list alternate part numbers for the same valve in different packaging: 528MCM, 528MPK, 528MFL and 528MFR for the Platinum, and 528CM, 528PK, 528FL, 528FR and 528RM for the base 528. Fluidmaster’s 400CRP14 was not found on Fluidmaster’s shop or product sitemap, so this page cannot say what it is.
How high does the valve sit, and where does the water stop?
Both makers publish the same two numbers, which is why brand matching buys nothing.
| Check | Fluidmaster 400H guide | Fluidmaster 400A guide | Korky 528MP and 528 pages |
|---|---|---|---|
| Top of fill valve cap above top of overflow pipe | Roughly 3 in | Roughly 3 in | Not stated |
| Top of overflow pipe below tank lever hole | At least 1 in | Not stated | Not stated |
| Water level after the tank stops filling | Roughly 1/2 in below the top of the overflow pipe | Roughly 1/2 in below | Water level mark on the valve 1/2 in below the top of the overflow tube |
| Raise the level | Turn the tank water level screw clockwise | Clockwise | Not stated |
| Bowl water level | Separate dial, pre-set for most toilets | No dial shown | Not stated |
| Refill tube | Clip to the overflow pipe; cut the tube if it will not fit under the lid | Clip to the overflow pipe; cut if too long | Ships with refill tube and clip |
| Locknut and supply connector | Hand-tighten only | Hand-tighten only | Not stated |
Fluidmaster’s 400H guide warns that the float cup must not touch the tank walls, the lever or the flush valve, and that over-tightening can crack the valve or the tank. Neither maker prints the shank thread size in inches on the pages opened, so this page does not either.
Which toilets need the OEM valve?
No source opened this session says a named toilet model requires its own maker’s fill valve. That is a gap, not a finding: Kohler’s and American Standard’s fill-valve pages timed out or returned 404, and Danco’s site returned 403. The one hint of an exception is Fluidmaster’s own 703A, which its instruction index files as the fill valve “for Glacier Bay/Niagara”, so a Glacier Bay tank is the one to open and look at before ordering a 400H.
How often does a fill valve need replacing?
None of the pages opened prints a replacement interval. The trigger is a tank that refills on its own or a valve that never shuts off, and the running toilet leak test tells you whether the fill valve or the flapper is the part at fault before you buy either.
Measure the overflow tube, then buy one valve
The Fluidmaster 400H is the wrong part for a tank whose overflow tube sits below its 9 inch minimum; the Korky 528MP reaches down to 8-1/2 inches. Neither is a like-for-like swap for a Glacier Bay tank fitted with the valve Fluidmaster’s 703A replaces. If your toilet is a TOTO, its own parts store sells the universal TSU99A.XR, so a universal from either aftermarket maker is the same class of part.
Frequently asked questions
Do I need a Kohler or TOTO fill valve for a Kohler or TOTO toilet?
Not on the evidence the makers publish. Fluidmaster's 400H page names Kohler, American Standard, TOTO and Glacier Bay among the brands it fits, Korky's 528MP page says it fits 99% of toilets, and TOTO's own parts store sells one Universal Fill Valve Assembly, TSU99A.XR, for both the Drake CST744S and the Carusoe CST714. No Kohler or American Standard page stating an exception could be opened this session.
How high should a toilet fill valve be set?
Fluidmaster's 400H and 400A guides say the top of the fill valve cap should measure roughly 3 inches above the top of the overflow pipe, and the 400H guide adds that the top of the overflow pipe must be at least 1 inch below the tank lever hole. The 400H adjusts from 9 to 14 inches, the Korky 528MP from 8-1/2 to 14 inches.
Where should the water level be in the tank?
Roughly 1/2 inch below the top of the overflow pipe, per Fluidmaster's 400H and 400A guides, and Korky's 528MP and 528 pages give the same 1/2 inch figure for the water level mark on their valves. On a Fluidmaster, turning the tank water level adjustment screw clockwise raises the float and the water level; counterclockwise lowers it.
What is the refill tube clip for?
It holds the refill tube on the rim of the overflow pipe so the tube refills the bowl during the tank fill. Fluidmaster's 400H guide says to attach the clip to the overflow pipe and, if the tube is too long to fit under the lid, to cut it and reattach it to the refill port. Korky's valves ship with a refill tube and clip as well.
What is the difference between the Fluidmaster 400A and 400H?
The 400H PerforMAX page lists a 9 to 14 inch adjustment, a 1.28 to 3.5 gpf rating and a separate bowl water level dial that its guide adjusts independently of the tank level screw. The 400A guide shows only the tank water level screw, and the 400A's height range in inches was not printed on any Fluidmaster page that opened this session.
Fact sheet and how to cite this page
- Answer
- Fluidmaster’s 400H page: adjustable from 9 to 14 inches, fits 2 inch and 3 inch flush valves on Kohler, American Standard, TOTO and Glacier Bay; Korky’s 528MP page: adjusts from 8-1/2 to 14 inches, fits 99% of toilets. Both set the water level 1/2 inch below the top of the overflow tube, and Fluidmaster puts the cap 3 inches above it. TOTO lists one valve, TSU99A.XR, for the Drake CST744S and the Carusoe CST714.
- Applies to
- Fluidmaster 400H PerforMAX (9 to 14 inch adjustment, 1.28 to 3.5 gpf)
- Fluidmaster 400A and 400A brass shank (height range not printed in inches)
- Korky QuietFILL Platinum 528MP and 2X Long Life 528X (8-1/2 to 14 inch adjustment)
- Korky QuietFILL 528 (range not printed in inches)
- TOTO TSU99A.XR Universal Fill Valve Assembly
- Compatibility basis
- Fluidmaster’s 400H PerforMAX product page and Quick Install Guide, Fluidmaster’s 400A Quick Install Guide booklet and installation-instructions index, Korky’s 528MP, 528 and 528X product pages, and TOTO’s parts store listings for the CST744S and CST714
- Assumptions
- Kohler, American Standard and Danco fill-valve pages could not be opened this session (timeouts, 403 and 404), so their OEM cells read not published and carry only the aftermarket maker’s own fit claim.
- Fluidmaster’s dedicated 400A product page and its single-pack 400A instruction PDF returned 404; the 400A figures come from the 400A booklet linked for the 3-pack on Fluidmaster’s instruction index.
- Neither Fluidmaster’s guides nor Korky’s pages print the shank thread size in inches, so this page does not state one.
- No maker page opened this session names a toilet model that requires its own fill valve instead of a universal one; the absence of such a statement is reported, not treated as proof that none exists.
- Method
- Adjustment ranges, fit lists, part numbers and installation dimensions copied from each maker’s own product page, installation guide or parts store. OwnerSpec installed no valve and measured no tank.
- Primary source
- Fluidmaster, 400H PerforMAX Quick Install Guide (PDF): cap 3 inches above overflow pipe, overflow pipe 1 inch below lever hole, water level 1/2 inch below overflow pipe (manufacturer or vendor document)
- Facts verified
- Last updated
- Cite as
- OwnerSpec, "Toilet Fill Valve by Model: Fluidmaster 400H and 400A, Korky QuietFILL 528, and What Kohler, American Standard, TOTO and Glacier Bay Tanks Take", https://ownerspec.com/plumbing/parts/toilet-fill-valve-by-model/, facts verified 27 September 2026.
Every figure above also appears, with its source, in the article. All sources ยท How OwnerSpec verifies numbers
Sources
- Fluidmaster, 400H PerforMAX Fill Valve product page: adjustable 9 to 14 inches, 1.28 to 3.5 gpf, fits 2 inch and 3 inch flush valve toilets, brand list (manufacturer or vendor document)
- Fluidmaster, 400H PerforMAX Quick Install Guide (PDF): cap 3 inches above overflow pipe, overflow pipe 1 inch below lever hole, water level 1/2 inch below overflow pipe (manufacturer or vendor document)
- Fluidmaster, 400A Fill Valve Quick Install Guide booklet (PDF, linked for the 400ACN 3-pack): cap 3 inches above overflow pipe, water level 1/2 inch below, adjustment screw directions (manufacturer or vendor document)
- Fluidmaster, Installation Instructions index: current 400H, 400A, 400A brass shank, 400LS, 400ACN and 703A Glacier Bay/Niagara instruction PDFs (manufacturer or vendor document)
- Fluidmaster, K-400H-043 fill valve and 2 inch/3 inch flapper kit product page (manufacturer or vendor document)
- Korky, QuietFILL Platinum Toilet Fill Valve 528MP product page: adjusts 8-1/2 to 14 inches, fits 99% of toilets, water level mark 1/2 inch below overflow tube (manufacturer or vendor document)
- Korky, QuietFILL Toilet Fill Valve 528 product page: twist-lock adjustment, universal fit, water level mark 1/2 inch below overflow tube (manufacturer or vendor document)
- Korky, 2X Long Life Toilet Fill Valve 528X product page: adjusts 8-1/2 to 14 inches (manufacturer or vendor document)
- Korky, fill valve replacements category page (528MP, 528, 528X and the R528 replacement cap) (manufacturer or vendor document)
- TOTO Parts Store, Drake Two-Piece Elongated 1.6 GPF CST744S parts: TSU99A.XR Universal Fill Valve Assembly and 3 inch flapper THU500S (manufacturer or vendor document)
- TOTO Parts Store, Carusoe 1.6 GPF Toilet CST714 parts: TSU99A.XR Universal Fill Valve Assembly and 2 inch flapper THU257 (manufacturer or vendor document)