Hurdy GurdyDesigned to stop wheel slipping for Semi Horizontal dropouts.Hurdy Gurdy is another nifty device that keeps a rear wheel from slipping forward in the dropout under pedal load. It's designed for our Cross-Check's semi-horizontal front-loading dropouts, and will also work on many other similar dropouts. Hurdy Gurdy is investment cast of stainless steel for durability and good looks, and shares many of Tuggnut's design features. Its two axle holes allow for a wide variety of fore/aft wheel positions, it will work with standard QRs, bolted axles, and nutted axles up to 10mm.Instructions:http://surlybikes.com//uploads/downloads/SUR_HurdyGurdy_Instructions_w.pdf