DeFender™ M2 has an ultra-secure quick release mounting system that easily adjusts from 25.4 to 34.9mm, easily fitting standard and oversized seat posts. The two-pivot arm articulates for improved tire coverage and perfect bike fit. A stiff engineering grade plastic support frame is comolded to a softer more flexible material at the trailing edge for greater durability. A highly polished underside helps prevent dirt buildup and aids in cleaning. Attachments QR Slip Joint Clamp Fits ø25.4 - ø34.9 mm Seatpost Adjustable Rear Angle Adjustable Material Two Tone Injected High Impact Resistant Plastic Added Features Highly Polished Underside Size (L x W x H) 40 x 10 x 12 cm Weight 230 g Fits Polygon Bikes: p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Trebuchet MS'; color: #000000; -webkit-text-stroke: #ffffff} span.s1 {font-kerning: none} Premier 4,5 - Xtrada 6,7,8 - Siskiu D5, D6, D7, T7, T8 Fits Marin Bikes: p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Trebuchet MS'; color: #000000; -webkit-text-stroke: #ffffff} span.s1 {font-kerning: none} Nail Trail 6,7 - Rift Zone 1,2,3