Made by DMM in 11mm narrow Dyneema Dynatech tape, these are closed sling "Express" type extenders with extra stitching and a rubber insert that make a stiffer quickdraw that are easier to clip in extremis as they hold the lower krab firmly.
They are ideal for both sports climbs and trad routes, but it is best to use longer ones for trad as there is less chance of the gear being lifted out of its placement.