Humboldt's Flame Test Burners are designed to be used as ignition sources for small-scale burning tests, such as the UL flame test and other similar test standards. Supplied complete with two 3/8" (9.5mm) ID by 4" (100mm) long mixing tubes for use in the 20mm and 125mm burning tests. Meets ASTM D5025. Provided with two tubes, one to lock out the air intake to produce a high yellow flame and the other can be adjusted for a sharp blue flame. Specifications: • Gas Type: Cylinder • CFH*: 3.85 • BTU Output*: 9,400 • Overall Height: 6" (152mm) *CFHs and BTU Outputs are figured on: 5 inch Water Column Pressures for Artificial and Natural Burners. 11 inch Water Column Pressures for LP Burners. Inlet OD for all Burners: 5/16" Serrated.