Wise BM1144-1B-990 Premier Series 36" Pontoon Seat Base designed as a precise fit with Wise BM1144-986, BM1144-988 and BM1144-989 Premier Series 36" Pontoon Bench Seat Cushion. (sold seperately) Constructed of high density rotational molded plastic that is mar, scuff and mildew resistant. Storage compartment with built in water drain holes. 5 Year Warranty. Base Dimensions - Length: 36", Depth: 19", Height: 11"