Gtechniq | Crystal Serum LightGtechniq Crystal Serum Light (CSL) is a professional grade ceramic coating that forms a hard, durable protective layer over your vehicle's clear coat, delivering long lasting gloss, chemical resistance, UV protection, and scratch resistance that wax and spray sealants simply cannot match. The coating bonds chemically to the paint surface, providing up to 5 years of protection when properly maintained, with a level of gloss depth and clarity that