Luminlay SBM SgM serieswith black pipe 60mm length (inner 25mm, outside 4mm, glow green)Products with Luminlay inserted in Black pipe The pipe material is hard so the sanding finish will be beautiful These products fit to maple or light colored wood fingerboards SBM serieslow BLUElong time glow type SgM serieslow gREENstrong glow type Luminlay mate..