These slides are made from premium hand pulled borosilicate tubing. Each slide is approximately 4mm thick and (72mm) long. Timely Limely is a premium slide with a transparent green color, that glows bright green when exposed to uv black light. CAUTION don't let this one take you over the edge, it tends to want to wander beyond the frets. These slides are also available in our (33mm) Lead Collection.