They are pricey, but they are built to withstand almost anything. I shot a oppossum out of a tree last year. The arrow passed through and continued out through many trees. I was able to locate the nock, still lit, laying next to my arrow and had exploded into two different pieces. I also shot three deer with them last year and they are all still going strong. As long as the circuit board is intact, you can buy replacement nocks to fit them into. Their intial cost is a bit expensive, but they will last a long long time.