This connector is for 1 AWG stranded, 1/0 AWG solid, and has a 0.91 in (23 mm) O.D.
The 3M™ Connector CI-1A is used with molded rubber splices 3M™ 5420 Series, 3M™ 5461 splice kit, and 3M™ 5450 Series. It has a connector O.D. of 0.91 inch and a minimum order case quantity of 10 each.