On the back side of the lamp is a small handle which can be pulled out to enable you to work “hands-free.” The lamp also includes a flashlight.
Testing for the tin side of float glass – why?
If painting silver stains or transparent glass paints on float glass (window glass), be aware that tin side of the glass affects these paints. Residual tin on the glass will increase the uptake of the silver stain – the stain will appear more intense after firing. Transparent paints may not have good color development because of the interaction with tin. Copper red must be painted on the tin side of float glass.
Test for the tin side with either the waterdrop method or use a short-wave UV lamp. The UV lamp requires that you test in a completely dark room. The tin side will glow with a milky white coating.