to the back portion 38 is formed from the second material the inner portion 42 extending from the traction portion 36 and extending to an defining the back portion 38 referring again to fig2 embodiments may include one or more edge treatments to reduce the effect of flame spread and wraparound from the traction portion 36 to the back portion 38 or vice versa in the embodiment of fig2 the belt edge portion 40 are formed from the fire resistant second material but in other embodiments may be formed from a different fire resistant material the edge portion 40 extends inboard partially across the traction portion 36 and or the back portion 38 it is desired to minimize the wraparound flame spread so that the fire resistance of the edge portion 40 is maintained while minimizing the impact on performance of the traction portion 36 in some embodiments the edge portion 40 extends laterally inboard about 3 mm but can vary according to desired performance the edge portions 40 may be formed in any one of several ways one method of forming the edge portion 40 is illustrated in fig4 in the embodiment of fig4 the edge portion 40 is formed oversized in both thickness 50 and width 52 and may be formed via for example co extrusion with the traction portion 36 the back portion 38 and the inner portion 42 or may be formed via a secondary extrusion or other process after forming the edge portion 40 is trimmed along trim lines 54 to.