Fits all types of singles records and turntables Made from glow in the dark plastic and is an perfect fit, non-slip and will snaps right in to your record For best results charge them under a desk lamp....the more you charge them the brighter and longer they will glow. The 45 rpm adaptor (also known as an 45 rpm record insert, or 45 rpm spindle adaptor) is a small plastic insert that goes in the middle of your 45-rpm record so it will play on a turntable. To activate the "glow in the dark" feature...simply place the adapters under a bright light for a few minutes and then turn out the lights to see them glow in the dark! The glow will last for over an hour with the strength of the glow based on the amount of light you charge it with. Can be re-used and re-charged over and over again.