Busch PROtective Busch PROtective CHE-1 4" Chin Extender for CRS-2 Universal Harness Busch PROtective CHE-1 4" Chin Strap Extender for CRS-2 Universal Harness The CHE-1 4" Chin Extender for CRS-2 Universal Harness along with Gas Mask use. $24.30 Choose Options Compare