Here's what other sites are saying:
The Quickstep 1-Step adjust etrier from Petzl is great from aid climbing. Equipped with a string, which allows the carabiner to be held in the major axis position(the strongest) and protects the carabiner attachment loop from wear.
Adjustable foot loop for easy ascension off fixed protection. Totals 7 feet 7 inches in length.. . . Attach to a fixed bolt, adjust for desired foot height, and simply step up. Made of 3/4-inch nylon webbing
An adjustable one step etrier that features rapid micro adjustment, the Quickstep Adjustable Etrier from Petzl has stiff foot tape to maintain an adequate opening and provide an essential single step that makes taking the hard route possible.
- Mountain Gear
Efficiency is essential on big aid routes, which is why the single-step Petzl Quickstep Adjustable Etrier utilizes a DoubleBack Buckle for quick and secure length adjustment. Plus, the adjustable strap in the foot loop prevents your shoe from slipping out.