Why Use Gtechniq C1 Crystal Lacquer? C1 is extremely easy to apply and ideal for someone new to applying ceramic coatings, or for someone who wants a coating that is durable, but not too much hassle to apply. With good gloss retention, C1 Crystal Lacquer becomes the functional surface of the cars paintwork, and if applied by a Gtechniq Accredited Detailer comes with a 5 year guarantee. C1 forms a crystalline film which is hard – this characteristic makes it effective at preventing minor scratching from poor wash technique on relatively soft automotive paint. The coating is good for gloss retention, but because it does not add much additional gloss it is ideal for matt paint finishes.