Comparison : Item # 645SZ450-3-32VDC, 645S Series - Solid State On / Off Motor Relays
Item # 645SZ475-3-32VDC, 645S Series - Solid State On / Off Motor Relays
Item # 645SR450-3-32VDC, 645S Series - Solid State On / Off Motor Relays
Item # 645SR475-3-32VDC, 645S Series - Solid State On / Off Motor Relays
Item # 645SZ450-90-280VAC, 645S Series - Solid State On / Off Motor Relays