The Dark Reader blue LED Hand Lamp and Spot Lamp are very versatile devices for viewing fluorescent samples around the lab. The lamps are very popular for viewing GFPs in transgenic plants and animals. Dark Reader Lamps use pure visible blue light as the excitation source and there is NO damaging and dangerous UV radiation to worry about. The blue light is especially suited for following fluorophors such as GFP and RFP as well as DNA stains such as GelGreen and GelStar. The Hand Lamp (HL34T) smoothly illuminates an area about 20 cm diameter (from a distance of 30 cm) and is ideal for use with bigger gels and larger samples in general.