A composition for peelable coating, which composition exhibits excellent properties such as film-formability and water resistance and can be dried at ambient temperature without any particular heating, to thereby provide excellent coating performance. The middle portion is suitable for abutting the digital flexor tendon of the horse. The upper control arm supports a spool upper ring and a spool shaft receiving member. The plurality of channels is configured to sustain substantial vertical loading and controllably deform under a predetermined threshold lateral crush load. It further includes a second electric path including a second set of thermocouples electrically connected in series, the number of thermocouples of the second set being smaller than the number of thermocouples of the first set. A method of making such a prism is also disclosed.