Size: 16.5VAC 40VA NPP1640P 16.5 V AC 40 VA Auto-Resetting (PTC) Fused Secondary 3 Prong Plug, Grounding Prong & Terminal. Efficiency Level VI Electrical outlet mounting tab UL & CE Listed, Wire Strain Relief, Lifetime Limited Warranty Typically used on alarm systems, gate openers, doorbells, etc. Compatible with but not limited to (Press Ctrl + F and search for your model): Honeywell Ademco 1361 ELK TRG1640 Honeywell 1361-GT MG Electronics MGT1640 PWS-1640 UTC 600-1023 GE Security 600-1023 Caddx 600-1023 UPG UB1640W