The difference between the Hardtail Covered Protection kit and the Steel Hardtail Covered Protection kit is the size and shape of the pieces that protect your frame. On steel hardtails, the shapes and sizes of the tubing are drastically different from the larger, rounder shapes you would find on a carbon or aluminum hardtail. So we decided to provide the best coverage possible for both of these rides by separating the two sets of hardtails into two different Covered Protection kits.