RSFR - commercial halogen-free marking tube, specifically designed for the special requirements of cable marking in high-speed rail, subway, and urban rail transit train sets, is made of environmentally friendly polyolefin heat-shrinkable material cross-linked by high-energy electron beam bombardment. The printed characters on the product exhibit excellent scratch and wear resistance. Even when exposed to cleaning agents or military fuel before and after heat shrinkage, the color code remains firmly in place, meeting the requirements of the US military standards SAE-AS81531 and MIL-STD-202F/215J, maintaining a permanent marking effect. It is primarily used in train sets, aerospace, tanks, and submarines.