[Linked Image from ecommerce.ilsco.com]
You must be talking about these. They are available from Ilsco and other manufacturers. This one (Ilsco) is available in 750MCM size with a 500MCM size pin. The offset variety, unfortunately, are available for aluminum only. www.ilsco.com/

[This message has been edited by Nick (edited 02-01-2002).]