The only lighted nocks that I have actually tried are Lumenoks. I never had any problems with them failing to light. My problem was that I had several of them break after being shot multiple times, Fortunately these incidents didn't occur when I was hunting. The first time it happened I told myself that maybe I'd done something to damage it. The second time I considered a possible defect. The third time it happened I tossed all of them Now I just stick to white blazers, white wraps and white nocks. I can see them fly just fine.