Quickdraw has use climbing
A quickdraw (also known as an extender) is a piece of climbing equipment used by rock and ice climbers to allow the climbing rope to run freely through protection such as bolt anchors or other  traditional gear  while leading.
A quickdraw consists of two carabiners connected by a semi-rigid material (sometimes called the "dogbone"). One carabiner has a straight gate and connects to an anchoring device. The other carabiner is for the climbing rope, and uses a bent gate. Quickdraws are manufactured with either a solid carabiner gate or a wire carabiner gate for its lighter weight.Use
A quickdraw is a specific type of runner. 
Runners are used by rock and ice climbers to extend the distance between an anchoring device and the rope.
A quickdraw is differentiated from a simple open loop of webbing with 2 carabiners on it by the following attributes: