Funny you bring that up - I went with these..hopefully 4mm is still alright for the 16awg wiring
http://www.ebay.com/itm/370145225835...ht_2558wt_1196
It would be great if a local airsoft retailer had these included in their electrical section of their site *winkwinknudgenudge*
I run buffer tube lipos so I use these to extend the rear wiring so im not fishing with my fingers to hook my batteries up.