A How are Slammer Integrated dock fenders manufactured? Slammer Marine fender products consist of three components: First: ½” x 3 5/8” x 40” mounting track produced from a high density polymer that has the pliability of plywood but remains impervious to water and harsh marine environments Second: the inner core consist of 40” sections of closed cell, impact absorbing foam, also impervious to water and highly resilient under constant impact Third: A removable 30oz PVC coated fabric providing a continuous and seamless enclosure for the 40” sections of foam. When the foam is inserted into the cover, the cover assembly, now an impact absorbing and cushioning body, then slides into the track. Slammer Marine can deliver any length fender between 24” and thirty (30) feet in total length. We recommend utilizing lengths of 10 ft and adjusting one or two fenders to be longer or shorter to meet the docks dimensional requirements.