The Sessionbag is our quiver bag. Fit your complete sail quiver. The session bag wave is based on quiver till 5.6 (mast till 430). The Freeride is based on quiver till 7.0 (mast till 490). The race one fit the entire big quiver bigger than 7.0. The universal wheel base, fits all size of the aero session bag and the Windsurf session board and session bag. Improved wheel base for easy carrying. Base is optional!