Help - Anyone Recognize This Drawbar Config???

Hello. I'm looking at a manual Bridgeport that's going to be for sale, but the seller was not the former operator of the machine. When going to remove the right angle attachment that is currently on it, found this. I'm only familiar with the common male hexagon drawbar. Does anyone recognize whats going on here? The inside bore is smooth and round. Not splined, keyed, female hex, etc - just smooth. And it's only about 3" deep with a flat bottom, it's not a through hole. I'm guessing it's related to some type of power drawbar that may have been removed? Or is there some type of cam-locking manual method I'm not familiar with? Thanks in advance for any help!

that's a pen Precise V5/V7: Pilot Pen

...Remove the right angle head (its clamped on to quill) than retract the Quill all the way up.....then you should be able to see the draw bar Hex to remove the mating Gear for the angle head.

DJ

Thanks DJ, but I'm still confused... doesn't the drawbar screw into the right angle head? Isn't loosening it the last step to release it? Even though the allen screws are loose, the quill is already all the way up as far as it can go with the right angle head attached (top of the right angle head is against the bottom of the mill head casting).

(good one on the pen, LOL)