The APEKS Spring Straps with Heel Pad have custom designed buckles that hold the straps in the optimum position for donning, doffing and when finning. Straps are equipped with a rubber heel extrusion that provide comfort while finning and the large heel grip tab makes for easy donning and doffing even when wearing thick gloves. Spring fin straps are depth compensating because they will compress to changes in the thickness of your boots. These corrosion resistant stainless steel spring fin straps come in three sizes (use the MD size for Small size RK3 fins.) Simple stainless pin design allows easy replacement of springs if necessary, making them a great save-a-dive-kit item.