This connector is a white, 4/0 AWG with a length of 2.750 in (69,9 mm), a 0.562 in (14,3 mm) I.D. and a 0.875 in (22,2 mm) O.D.
The 3M™ Scotchlok™ Aluminum Connector 20008 is for use with copper or aluminum conductors. These aluminum connectors feature color coded end caps for identification. Contact aid provided in connector barrel is compatible with poly/EPR insulations
Scotchlok Aluminum Compression Connectors - Data Sheet (PDF 37.2 K)