The Energy Saving Linear Halogen R7s tungsten bulbs have all the advantages of standard double ended halogen linear bulbs with the added benefits of 20% energy saving. General Benefits of Eco-Halogens: Saves 20% in energy and electricity costs compared to standard incandescent bulbs Like for like in size Fully Dimmable Instant Start Up 2000 hours average rated life. Lasts longer  compared to standard incandescent bulbs Brilliant sparkling white light with a colour rendering index (CRI) of 100 No mercury or other hazardous materials