Wedge-shaped components slide in for a snug, stable fit Type B seat mounts are designed to "lock" into the post Engineered to prevent unintentional detachment Heavy-duty bushing with peripheral bearing system and exclusive "crush ribs" are individually sized for exact fit Tubing is precisely-sized and satin-anodized finished Tubing comes in several styles. Pedestals come in several lengths, including patented "J-Slot" adjustable height Precisely positioned locking tab positively locks post to base Wedge bushing locks in with a tight, solid fit 2-Point stainless steel riveting strengthens the bushing Strong base design has reinforcing ribs and improved profile to withstand the toughest conditions Bead blasting closes aluminum porosity. Brushing process provides long-lasting high-sheen finish