One new old stock filter for your stereo, 2 way radio etc, 12 VDC (actually can do 6-15vdc so may be good for antique car 6v systems to help with ignition noise) These were surplus from some high end radio or GPS systems from years ago. A paper we found indicates the Orange black is the 12V input and the Red black is the 12 v output (not sure if it matters which way since it is an inline filter) Looks like they were originally marked the other way and then blackened out so maybe they found it works better this way. They have peel/stick on back (may not be sticky due to age) and 2 screw holes for easy mounting. New surplus, may have some dust, grime etc from storage. Corona update: We are working hard to ship most items out within one business day (ignore longer estimated time). Due to having only one person in the building, items are being shipped directly from sold page notification, not messages which may take longer to respond to. Therefore we are not able to respond to cancellation requests. PLEASE DO NOT ORDER AND THEN ASK TO CANCEL! Your order ships when paid. Also there are no returns (other than if an item is damaged in shipping) Thank You.