3 air chambers including inner auxiliary chamber inside main hull Quick-fill,fast-deflate Boston valve on main hull chamber Rugged vinyl construction All-around grab line Inflatable I-beam floor for comfort and rigidity Infltable cushions(3/4 models) Grab handles on bow Welded on oar locks Oar holders(2/3/4 models) U.S. Coast Guard I.D. TUV approved Repair kit Shelf Box #68355 Challenger 1 74" * 44.5" * 13" (188cm * 113cm * 33cm) 3 Ea.,27.8 Lb.(12.7kg) Material:17 Ga.(0.43mm) Capacity:175 Lb.(80kg) #68367 Challenger 2 Set 93" * 45" * 16" (236cm * 114cm * 41cm) 2 Ea.,38.1 Lb.(17.3kg) Material:20 Ga.(0.51mm) Capacity:440 Lb.(200kg) 49"(122cm) French Oras #68612 High-Output Pump #68370 Challenger 3 Set 116" * 54" * 17" (295cm * 137cm * 43cm) 2 Ea.,63.6 Lb.(28.9kg) Material:23Ga.(0.58mm) Capacity:660 Lb.(300kg) 49"(122cm) Aluminum Oras #68614 High-Output Pump #68371 Challenger 4 138" * 57" * 19" (351cm * 145cm * 48cm) 1 Ea.,41.2 Lb.(18.7kg) Material:30 Ga.(0.76mm) Capacity:880 Lb.(400kg)