Before i knew anything about rebuilding i bought a pack of the below item (50 of them for like $2.00 ) for Pro Tank rebuilds and didn't touch them for a long time because i found out how easy it was to wrap your own.
http://www.fasttech.com/products/3099/10007181/1591806-pre-made-wires-and-wicks-for-atomizer-50-pack
I was in a rush one day and didn't have time to rebuild so i just stuck the FT coil into the Protank head and to my shock , those things are not that bad .
I was very surprised by the vapor and taste of my juice with them , for how dirt cheap they are i think it was a good buy (especially if you like silica wicks). I still prefer to start from scratch and wrap my own but these definitely work .
The leg lengths are precision cut for Pro Tank heads , they come pre wrapped in ohm's ratings from 1.5 up to 2.9.