PRODUCT SPECIFICATIONS

GERBER GTB20958

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 numberGMX21958
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R5457C4

Original cell: GMX21958

FieldID: 7bb87b6cee255ddfb1e4d3bf274455f14d547eba8088624383f0d9e9f63e7a1f

EvidenceID: 1946725b92b7461bb21861f34011211dc0cdef0421ab90a98dadef853cfa44f6

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Brand as reportedGERBER
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R5457C1

Original cell: GERBER

FieldID: a94a7fc2891c635c4d1f988a54a18e8f356855ebc3866dc5ec2d993b0bbcdf81

EvidenceID: d2bd5d998afa1707b4cdf53688d15f0dc28f3ba7bdc105a75ffcc952a5fa7c4e

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Flush mechanismGravity
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R5457C8

Original cell: Gravity

FieldID: 5fab9ff4d85b2323afe530d455cf6c7997020f01a556a9a248a11ec58e7d5f9c

EvidenceID: 5c7c6965b3b522ba64feecca4f0fa983abc247e558317b09977b6d19cf39b5e3

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Flush typeSingle
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R5457C7

Original cell: Single

FieldID: 20c476a656a3e690bd7ffdfe4d11eb00ba4c231f6649e0f9ce2678f06ae203b1

EvidenceID: 1cea33d333bd4fccc03a29d3b94dd7331ef69918eaf201724a6f6af8921e95b1

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Rated flush volumevolume: 1.28 US gal/flush
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R5457C6

Original cell: 1.28

FieldID: c5e5b12fe9091fc8d00a90db9d2881443bc7ade6f2f77836bb751d71bdbaf2c1

EvidenceID: 5ea79be5c4ac015a8b108fff96e6b9eecbc3b94a30ae5b8f5be96e95f260a56b

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Source model nameMAXWELL®
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R5457C2

Original cell: MAXWELL®

FieldID: 5f1b3b7eab39bd24e1854a7a38c3adf0de31abda0f2311dea175ce8634707908

EvidenceID: 3d63f07314cebf523de7daaeaf95db6ad59ce9501c0a08ce9148803d39c5d5a6

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Source model numberGTB20958
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R5457C3

Original cell: GTB20958

FieldID: fcb051118f1f235ac96d83a177c6b240886ee7358a9f93800b0476ab2aab2ccd

EvidenceID: b31f38500babd5c056a9878fdc544810eba7d5c97ae7402cb007463fa7aaac33

Raw SHA256: 577fa416addade9df0ee69c78d9e7c46ac4098b933286d2515e1bb18f8ca78ef

Source tank model numberG0028990
Field source

ZIPCSV:WaterSense-Products-TankTypeToilets.csv!R5457C5

Original cell: G0028990

FieldID: 9ccc196da8163ee8bc747563b214e29d13c59a3f767ca8ccd130c173e4604bd1

EvidenceID: 7f19dff5341523a4e0e75f8537e2a30afb520ea3cde0b1de4a4fc3f32223ca8f

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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