Laser technology Laser HP LaserJet Color 5550 Printer, Laser, Colour, 600 x 600 DPI, A3, 28 ppm HP LaserJet Color 5550 Printer. Print technology: Laser, Colour. Number of print cartridges: 4, Maximum duty cycle: 120000 pages per month. Maximum resolution: 600 x 600 DPI. Maximum ISO A-series paper size: A3. Print speed (black, normal quality, A4/US Letter): 28 ppm