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 * Precisely positioned locking tab positively locks post to base * 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 * Tubing comes in several styles.Pedestals come in several lengths, including patented J-Slot * Wedge bushing locks in with a tight, solid fit. 2-Point stainless steel riveting strengthens the bushing