these ended on ebay today. I dont know if my oval has them or not. Are they rare? have I missed a bargain?

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&rd=1&item=140090398943 

they are the diffusers on the back of the glass tail light lenses.
if you look inside your taillights and can see a plastic looking thing stuck to the inside of the glass with all these parallel lines on it then thats it
i guess they are as common as oval tail lights. no need to replace yours unless they are rooted/missing.

does anyone know if the lights work properly without these?