Adapter for charging (filling) Benjamin 4,500 psi carbon fiber tanks Male Foster nipple connects to the fill station on one end and a 300-DIN male adaptor that connects to a Benjamin carbon fiber tank (model 81001 or 81002) When you take your carbon fiber tank to be filled, you'll need a connector (adapter) to attach to the DIN valve on your tank that will fit the compressor at the place that fills your tank. This adapter should be a perfect match, but it's a good idea to contact your fill station in advance to make sure this adapter is the one you need to attach to their fill system.