Covered under Edwin McClain’s December 1928 US patent, this Hagen sand wedge has a dramatically curved face and a large, broad sole.  Bobby Jones even used one of these in the 1930 British Open.  In 1931 the USGA adopted a new regulation that made any club with a concave face non-conforming.  Consequently, Hagen stopped producing its concave sand wedge.

This example, complete with its 34" shaft and original leather-wrapped grip, appears to be nearly unused. All the chrome is still shining like it did 90 some years ago.  A beautiful example of this always popular collectible.

TCA2 Vol. 1 p. 283-284

This club is easily recognized in both of the accompanying group images.