These connectors come with absolutely no assembly instructions which might surprise some. Assembly is self evident however. All that you really have to do is solder-sweat the heavy gauge wire into the 'pot' on the end of the connector tip. It is a good idea to puddle some solder into the pot and then lower the tinned wire into the pot. It may be necessary to apply some more heat (usually with a small gas torch or stove gas top)to get the whole lot to melt. Try to keep the joint immobile until the solder 'sets', then cool off under tap water. And of course you can always crimp the lead into the solder cup, but this should really be done professionally. A piece of heat shrink tidies the job nicely. The wire/lug/contact then just snaps into the housing.