PRODUCT SPECIFICATIONS

Gerber GLF21551(LF-21-551)

Source rating — not measured installation performanceRecorded rating (US gal/flush)Recorded rating: 0.801
Chart generated from this record's EPA snapshot fields. Shared zero baseline; units shown above. This is not a measured flow or flush test.
Tank recordBowl record
Component identification schematic, not to scale. No installation dimensions or compatibility approval are implied.

Compare recorded specifications

Same source category and product or flush type. These are source-record comparisons, not compatible replacements or performance recommendations. Equal ratings do not make two models identical.

Historical EPA source fields; unknown values remain unknown
ParameterGerber GLF21551(LF-21-551)Gerber GWS20918(WS-20-918)Premier 1034395American Standard 3471128.XXX
Source model nameVIPER®MAXWELL®Not suppliedHorizon
Rated flush volumevolume: 0.8 US gal/flushvolume: 1.28 US gal/flushvolume: 1.28 US gal/flushvolume: 1.28 US gal/flush
Flush typeSingleSingleSingleSingle
Source bowl model numberGWS21551(WS-21-551)GMX21928(MX-21-928)N2442EB3061101R.XXX
Source tank model numberGLF28580(LF-28-580)G0028990(28-990)N2442T4061428R.XXX
Flush mechanismGravityGravityGravityGravity

Model specifications

Recorded in the EPA directory snapshot of 2026-10-30
ParameterRecorded value
Source bowl model numberGWS21551(WS-21-551)
Brand as reportedGerber
Flush mechanismGravity
Flush typeSingle
Rated flush volumevolume: 0.8 US gal/flush
Source model nameVIPER®
Source model numberGLF21551(LF-21-551)
Source tank model numberGLF28580(LF-28-580)

Full and reduced flush volumes remain separate. Counts of uses are needed to estimate consumption; compatibility and installation conditions are not provided.

Source: EPA WaterSense directory. Sources & Methods.

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Same category and recorded type; these are navigation examples, not recommended substitutes or compatibility matches.

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