SRAM PC 1091 HollowPin 114 Links 10 Speed 2013
The 1091 is basically a little heavier and little more durable the the 1091R. It weighs about 10 grams more and does not have the Lightening Hole in the plate. For ease of install and removal SRAM includes the Power Lock.
The SRAM PC 1091 is a strong, reasonably light chain that gives precise quiet shifting for 10 speed systems.