Details: Simple Sizing - only two sizes - Medium (up to 16") neck and Large. You can use a large even if your neck is smaller to give more room over a collar bone. Angle Independent - the small, low collar works perfectly with any seating angle and does not interfere with the seatback. The articulating collar rises in an impact to create the optimum tether angle. Perfect for drivers with multiple cars Load controlling "bump stop" - the legs are connect to the collar along with a unique bump stop that smooths out the initial tether loading and allows proper collar angle Floating Tether - the floating tether allows a full range of motion of the head to the left and right while also adding some side stability Flexible legs - the legs of the FLEX have the padding molded in eliminating the need for additional pads. This allows the belts to fit tight to the body and keeps the FLEX from moving under the belts Retention ears - the collar features extended vertical ears at the outside edge that help to keep your belts on the FLEX even in a secondary impact. Slip-Stop - mate your FLEX with SCHROTH Slip-Stop shoulder belts for intensive off road and rallye applications. Slip-Stop shoulder belts have a counter groove on the back of the belt that fits with groves on the top of the lower legs of the FLEX. Includes FLEX helmet posts that mount directly to the M6 nut in your helmet. Features: SFI 38.1 Certified High strength Carbon reinforced materials Angle independent low collar design Dynamic articulating collar Rate responsive bump stop Sliding "twist anchor" tether system SlipStop belt retention system Integrated shoulder padding system Form fitting lower legs