3M(TM) Electrical Spring Connectors 512, Red, 250 per jug, 5000 per case 2-10#18, 2-7#16, 1-6#14, 1-5#12, 1-3#10, 1-2#8, 1#6 AWG. Designed for speed and efficiency, these connectors spin-on quickly and tighten-down easily. They're engineered for easy back-off, too. The live inner spring action delivers uniform holding power.