HP - C3906A LaserJet Toner Cartridge with microfine Black Toner. LaserJet 5L/6L/3100/3150. 2500 page life. Designed for LaserJet 5L, 6L and 3100 series printers, this HP 06A Black Toner Cartridge (C3906A) is packed with high quality HP toner for the best possible results. The toner is compatible with low temperature operation for lower energy costs and better productivity. This cartridge comes with enough toner to print up to 2,500 pages - and because it's a genuine HP cartridge, you get unbeatable reliability when you need it most.