Change in focal length and concentrating width of the Halogen Line Heater HLH-55/f25 HEAT-TECH info 8 years ago This video is a demonstration to confirm the concentrating width of the Halogen Line Heater HLH-55/f25. Related page: Change in focal length and concentrating width of the Halogen Line Heater HLH-65/f75 Change in focal length and concentrating width of the Halogen Line Heater HLH-30/f20 Pet Resin bottle heating with halogen line heater Follow up performance of the Air Blow Heater Evaporation of water Branding and Stencil of wood Focal length and focus diameter of the Halogen Pont Heater HPH-60/f60 Focal length and focus diameter of the Halogen Pont Heater HPH-120/f45