Spider Steel Mortice Key Lock Complete Set With Chrome Plated Finish (S606MCP + RML4) S606M (CP) - Steel Mortice Handles, KY Small, Finish Chrome Plated, Door Thickness 30-45 MM, Metal Steel. RML4 - KY Mortice Locks, Metal Steel / Zinc, Size 65 MM, Door Thickness 30-45 MM, 4 Steel Lever, Finish Electro Coated Body & CP Cram, Durable and Long Life, Good Quality Mortice Lock Set From Renowned Brand Spider.