Honeywell 621-3502 Description Description Honeywell 12-24V DC Fast Response Input Related products HONEYWELL AX51-051-001 HONEYWELL 621-6550 HONEYWELL 620-1690 HONEYWELL 621-0010 HONEYWELL 621-9934 HONEYWELL STD924-A1A-00000-MB.3H+XXXX