These types of bands are outside serrated, which allows the inner surface of the band to remain smooth, preventing any insulation damage when tightening the bands. The width of the band allows for increased contact surface with the cable, which further minimizes the risk of damage. PE / RPE bands have E.D.F. approval. Their special design allows for a flat profile head, making them suitable for use in tight spaces. RPE bands are expandable and designed for multiple use. PE / RPE bands were specifically designed for use in the power industry. However, they are used in many other fields, especially in areas with limited space, such as tying hoses or cables in narrow shafts or channels. Colored versions are used for securing covers in children's playrooms.