This is an energy efficient Kosnic 21w 2D (EXUN-DD/E) lamp with a 4 pin base (GR10q) and has an average life of 12,000 hours in colour 835 standard white (3500K). We are confident we are the cheapest online for this lamp because we price check daily. If you have a 21w 2D 4Pin type lamp you must replace it with the same wattage. You cannot raise or lower the wattage. We package our 2D lamps very carefully to avoid damages in the post. We sell thousands of these types of lamps yearly and we have less than 1% damage rate for your peace of mind.