Wheels Manufacturing Derailleur Hanger - 21 MFPN=CS-3 Guru Super Hallgeir is a

Guru Super Hallgeir is a harder version of Hallgeir extreme for colder conditions

which has undergone a redesign

Compatible only with Cane Creek HELM forks

Additionally

Wheels Manufacturing Derailleur Hanger - 21 MFPN=CS-3 Guru Super Hallgeir is aWheels Manufacturing Derailleur Hanger 21. Wheels Manufacturing hangers are stiffer than almost any OEM hanger which improves durability and shifting performance. OEM hangers are only produced by a handful of manufacturers mostly in Taiwan and China. As a result you will see many bikes with exactly the same hanger. Bicycle manufacturers may make mid year changes. Please use the hanger photos to select the proper hanger for your application. These