Primarily used in catering for maintaining heat within food on hot plates, heated counters, gantry and serveries.They are available in their \"Bare\" or \"Jacketed\" form. It is recommended that all catering facilities use jacketed versions. The additional quartz glass sleeve protects the tube inside from any outside contact that may cause hotspot light bulbs and early failure but more importantly in the event of a light bulb shattering, glass shards will be prevented from falling into food.These infrared linear light bulbs have many other applications where a compact heat source is required. Space heaters, Drying processes, Thermoforming, Shrink packaging, Vulcanizing and curing rubber, Laminating, Sealing and electrostatic copy equipment.Please check the length of the light bulbs before ordering as most are available in 118mm as well as 220mm.Short wave Infrared. 92% of electrical output is radiation (8% light output). Radiation maintains heat within the food. Free moving glass sleeve protects the light bulb inside. No warm-up costs.Fitted with R7s round (7mm) caps to each end.