The GM Rod Post SP is a simple spinning rod compatible rod post that can be easily attached to fishing vests, waist bags, belts, etc. From "landing" to "wading", by using the GM rod post SP during "lure change" and "landing", both arms are freed and stress is greatly reduced.Inner diameter 40 mm .The reel mounting holder is W16mm.Supported belt size Width: 25 mm to 50 mm / Thickness: up to 3.5 mm Accessories: Main body fall prevention original carabiner and spiral rope (200 mm)