One of our chargers is used on the GM Canada loco which is called a 'Class 66' in the UK. There is also a faster version called the 'Class 67'.
The battery connector is made by a company called Pyle National, part of Amphenol.
The charger connector body has a mixture of brass, plated steel and aluminium (aluminum) parts, and within almost days it is almost impossible to disassemble as there is galvanic corrosion between the parts. Took one out of the box the other day (we are shipping a couple of chargers up north tomorrow) and it had already started to seize up. The other thing that bugs me is that they will use fine threads on these parts of the body that have to come undone, and of course they don't...
We make our own charger connectors now, out of solid stainless steel, and avoid any such problems. We haven't cloned the Pyle unit yet, but the condition they get into in outdoor railway use has to be seen to be believed! This is a part that they quote $US500.00 each for.
Peter