The Madshus Contour Biathlon Strap is a high performance but straightforward 3-D Moldable strap. A silicone grip pattern on the inside of the strap also helps keep the strap in place. The 3-D molding and contouring also hold the strap open while getting in and out of your pole between shoots. Straps are left/right.
One size fits all.
To mold just warm with a hair dryer for a minute, insert gloved hand, tighten/adjust velcro strap and let cool.