Honeywell 621-9940 Description Description Honeywell Serial I/O Module (8/16/32 Point) Related products HONEYWELL 621-0010 HONEYWELL STD924-A1A-00000-MB.3H+XXXX HONEYWELL 621-3550 HONEYWELL 621-3552RC HONEYWELL AX51-051-001 HONEYWELL 621-6550
