Specifications for Safariland 6004 SLS Tactical Holster – Tactical Black, Left Hand 6004-193-122. Category: Duty / Tactical Holsters. Note: (W/ Bobbed Hammer). Fits: Heckler & Koch – USP 40, USP 9. Heckler & Koch – USP 45. Features the SLS (Self Locking System) rotating hood system. SLS allows for a smoother, single-motion draw and greater protection against attempted weapon takeaways. Thermal-molded SAFARI-LAMINATE construction protects handgun and sights. Standard double leg strap and leg shroud with mounting holes for optional accessories.