Check the listing for details. REI Climbing Harness Size M, ? No Tag. Condition: For parts or not working. Listed at 30.00 USD. The product is a medium size climbing harness made by REI. The harness is designed for outdoor sports like climbing and caving. It does not have a tag indicating its specific size, but it is suitable for a waist measurement of. This harness provides a secure and comfortable fit for climbers, allowing them to focus on their outdoor adventure without worrying about safety concerns.