Main Features
1)  Axial surface of oval-shaped lock has a minimum abrasion for device when connecting widely spaced metal part,like pulley,upper part of ascender,rope clamp etc.
2)  Screw-lock system (SL) works stably and reliably in dusty,muddy or icy condition,suitable for infrequent door opening and closing.
3) Anti-snag system prevents it from catching clothing and fittings,reducing risks of and increasing descending speed.