IEC 60684-3-211:2007 gives the requirements for four types of semi-rigid, heat-shrinkable polyolefin sleeving with a nominal shrink ratio of 2:1 that has been found suitable for temperatures up to 135 °C. Type A: general purpose, flame-retarded, opaque colours; Type B: general purpose, non flame-retarded, translucent; Type C: fluid resistant, flame-retarded, opaque colours; Type D: fluid resistant, non flam-retarded, translucent. The major technical changes with regard to the second edition concern a better alignment with existing national specifications.