PRODUCT SPECIFICATIONS

Gerber GWS20918(WS-20-918)

Source rating — not measured installation performanceRecorded rating (US gal/flush)Recorded rating: 1.2801.5
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.

Model specifications

Recorded in the EPA directory snapshot of 2026-10-30
ParameterRecorded valueSource
Source bowl model numberGMX21928(MX-21-928)
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R2122C4

Original cell: GMX21928(MX-21-928)

FieldID: 5c385cf5a111ff67a4d469dfea9f916180c39b114bcb100fdc63392352a9e16e

EvidenceID: 9ead9f9204baea1b33f3d79ca96a56fe3002f843dee46be04fec3f9b2b95e382

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Brand as reportedGerber
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R2122C1

Original cell: Gerber

FieldID: 377c5d1f8b359dabf062db93ae5911f96158527cd488686ddb18ae407bb70e5f

EvidenceID: 62d64fc496b9f2995f5899827daf7c126b901ba33b40626739d7d2b0a6fd6c3e

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Flush mechanismGravity
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R2122C8

Original cell: Gravity

FieldID: 2115e627a5dadad049dc06f45a14054b21cb44d01f5fcf4f74467ff5037c1c99

EvidenceID: d42186a8555ac98760ad2c4af6485ca84059b3973cca96c9071de632c3170dff

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Flush typeSingle
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R2122C7

Original cell: Single

FieldID: dfac89f23739670ef31632bc480d36f977abe8917b274365fc8ebbf8ee099b86

EvidenceID: c70898b413e29117358e3c1af9e9e4fa961f2e220f336538c92d8e88a729cc34

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Rated flush volumevolume: 1.28 US gal/flush
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R2122C6

Original cell: 1.28

FieldID: 4e4a84a0097fc7301ead3418850cf17766608ab5e310e2386f0c7d9a2239fcfb

EvidenceID: 7c18521cfd8dcb2c2be5b0405205c08a03ebf12820f15d83bb0afd1d98db9f0c

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Source model nameMAXWELL®
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R2122C2

Original cell: MAXWELL®

FieldID: 5416e0493b64745f4bc656295d2ecb93777d28fd840a10cdb5648b38a5f92964

EvidenceID: edd37fbd5d38ed3c21ef5f2c1866b8b68574422ffd450053ac2d1cd5767d8a31

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Source model numberGWS20918(WS-20-918)
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R2122C3

Original cell: GWS20918(WS-20-918)

FieldID: 2b2ad7db15e159dc16b0c7c31a74ab47b99797d4307e42a62cecb74c497fd089

EvidenceID: 36bfefcd58602133ad0c539a6fc9d311fda4829c5954e4b86f4cbd7c0dfc5dcf

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Source tank model numberG0028990(28-990)
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R2122C5

Original cell: G0028990(28-990)

FieldID: 1393b7ac17a2f33f2e55c9df8f22661324bc6fdaa6ac8bb86ea3633fc185a977

EvidenceID: 3bd8b74ef6d843afa953e0a1060b994872fa7818a314df809e44613ac640dd06

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

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

What this record can — and cannot — answer

Use these fields to identify the source model and compare the same type of recorded quantity. This historical record does not establish current certification, sales availability, price, installation compatibility or measured performance in your building.

Official source: EPA WaterSense product directory. This is a category-wide source, not a model-specific product or purchase link. Read the source and methods notes.

Other source models to examine

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

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