THERMALITE BAR PLUGZ - Features: Unique design w/ Thermalite for durability. In-molded Steel insert to eliminate bar punch through. Expands securely with a grub screw to fit tightly on regular, 9, 11, & 13 butt bars. - Material: THERMALITE™. - Color: Black. - Weight: 1.0oz. (28.35g.) per pair.