For the price, this bill head is a great deal! It is very straight and it is well tempered..
A note concerning the diameter of the socket: while it states 1 3/8 inch size, the INNER diameter is around 1 1/4 inch at its thickest. Hopefully this info helps when trying to taper a pole or handle to fit.
Overall it is a great value, considering that Medieval/Renaissance billhooks are hard to come by unless custom made. I highly recommend this head.