The lighter knob in the pic is missing the element. You need to slip the chrome bezel (part 2) over the housing (part 3) and mount it in the dash. Then the retainer (part 5) screws to the socket from behind the dash. The forth part is a lamp socket, and will only work with the retainer in the pic. I forgot to mention that this is a '69 cig lighter. I'm sure this was used for many years of GM cars. The knobs changed from year to year, but the housing & retainer should be the same. This is a spare I don't need. I think the chrome bezel is for '69 only. I haven't been able to find a pic of a '68 dash to confirm this. If interested, $10 plus shipping. PM me if interested. Oh, the lamp socket is not included. For now

Tom

Tom
’69 Firebird 400 4spd conv
’69 Firebird OHC 3spd coupe