Kroy 2470021 Black on White Cartridge for 1/4 Inch Shrink Tube-by-Kroy Flexible polyolefin tubing and thermal transfer resin ribbon in a cartridge. Shrink ratio 3:1. Operating temperature range of -67? to 275?F (-55?C to 135?C) with up to 347?F for short duration and low recovery temperature of 194?F. All tubing is flame resistant; Chemical and water resistant. Meets Military Specification MIL-DTL-23053/5C Class 1 and 3, UL-224 VW-1 rating.