Never search for the right detent ball spring again. Save your valuable time, and money, with this Kit of correctly-sized "in-the-hole" coil springs - a perfect match for each and every size contained in our Detent Ball Kit. You get 20 each of eight springs to match the eight most popular sizes of detent balls used in the gunsmithing industry. The springs are made with two "closed" (finished) ends and enough length that one spring can usually be made into two; a double value. Mfg: Brownells SPECS: Tempered steel. " long. Refills sold 20 per pak.