These PVC Butt Connectors are the most economical insulated terminals available.   They feature a PVC insulationed sleeve that is securely fastened to the seam barrel.  They offer a flared entry to easy wire insertion and industry standard color coding for wire sizes.  Red 22-18 Guage Wire, Blue 16-14 Guage Wire, and Yellow 12-10 Gauge Wire. 

Solds in kit with 5 connectors in each kit.  Combo kit includes 2 Reds, 2 Blues, and 1 Yellow Butt Connector.   All other kits include 5 of the same color/size connector.