What type "red" bulbs do I need to go with for my clear, rear side markers? I don't know the difference between single and double filament. I checked the manual, but the listing there don't match up with the lingo on the AutoDynamic website.

I bought some before but don't recall what type they were. I was not please with them, either. One of them, the red bulbs ordered before, is now white.

Here are my choics:
http://www.autodynamic.com/optiblue_...hite_bulbs.htm

M3:
12 Volt, 21/5 W Plug In Type, US Type 7443
Double Filament

M21:
12 Volt, 5 W Plug In Type, US Type 168
Single Filament

M23:
12 Volt / 21 W, Push In Type Single Filament

Any suggestions?