Original Item: Yes, that is what it is called. It is used to hold the grip assembly to the receiver body, along with an item called the Joint Pin. The T pin is quite different, however. Like the Joint Pin, it is inserted from the left to the right, but it does not require a nut. Rather, it threads into the grip body itself. The cross handle which gives the pin its name is used to provide torque for screwing and unscrewing, and one end of the handle is rebated and provided with a concave tip. It is meant to be used as a drift to drive out the Side Levers Split Pin during disassembly of the lock.