MICRO SWITCH GKE Series Dual Entry Key-Operated Safety Switch, 2NC Direct Opening, Slow Action, 20 mm, Plastic, Silver Contacts The GKE Series safety key-operated switch provides superior reliability for safety hard guarding applications in a compact, cost-effective package. The GKE conforms to IEC 60947-5-1 and carries the cULus, CE, CCC, and SIL 3 capable approvals.