Friends, I tested my 16mm Park "Peanut Butter" wrench with three different cranksets - Campagnolo NR and Gran Sport and a Sugino Mighty Competition. It would not work with any of them. How sad... So it seems you must use the Zeus wrench, a modified socket or perhaps an unmodified Snap-On or Stahlwillie socket. (I don't have those in 16mm but after examining the 15mm and 17mm sockets I hve from those manufacturers, it seems like their 16mm versions should work. No gaurantees thre of course.) Cheers, Fred Rednor - Arlington, Virginia