NSi Industries Aluminum Splicer Reducer 4/0-6 AWG 4/0SR - The Home Depot
Gardner Bender WingGard Medium Red 22 AWG to 6 AWG Wire Connector (100-Pack) - McCabe Do it Center
Gardner Bender WingGard Large Blue 14 AWG to 6 AWG Wire Connector (50-Pack) - Parker's Building Supply
Amazon.com: 10pcs 6 Gauge 6 AWG x 5/16” Pure Copper Cable Lug Terminal Ring Connectors with Dual Wall Adhesive Lined Red + Black Heat Shrink Tubing – by WNI : Industrial & Scientific
Ideal 30-163 Blue Twist On Wire Connector 6 AWG to 16 AWG (15 Pcs)
Gardner Bender 6 AWG 3/8 in. Vinyl-Insulated Ring Terminals, Blue (4-Pack) 15-096 - The Home Depot
Polaris 3/0-6 AWG Insulated Tap Connector, Black IT-3/0B - The Home Depot
Gardner Bender Hex-Lok Gray 14 AWG to 6 AWG Wire Connector (25-Pack) - Anderson Lumber