This is a very good heavy duty ballhead. All of the reviews are very favorable. All of them prefer this over the RRS BH-55. I had the BH-55 myself, and to me, this is more intuitive. This particular head is well-maintained, smooth and there is no slip whatsoever when tighten. The head has seen use but I would rate it conservatively a 9.
The exact head with specs can be found right here:
SUNWAYFOTO XB 52 Tripod Ball Head Arca Compatible 132lb Max Load XB52 Sunway New | eBay
I have the regular screw-knob clamp and the duo-lever clamp. I don't have the box for the head but I will include a pouch to go with it.
I'm asking $330 shipped and paypal'd for the XB-52 + regular clamp, $360 shipped and paypal'd for the XB-52DL (duo lever), $390 shipped and paypal'd for the head and both clamps.
I'm selling this wonderful head because I'm looking to upgrade to the Arca D4 head.
Pictures of the ballhead and the two clamps and of the most "severe", noticeable blemishes on the head.