WEEB-6.7 Bonding Jumper for splicing WEEB-SPLICE Flexible electrical connection between mechanically spliced rails. Comes complete with 1/4" hardware and WEEB 6.7. Long rails for roof mount installations are sometimes constructed from two shorter rail sections with a mechanical splice. It is then necessary to also make an electrical splice, which can be done with a WEEB Bonding Jumper. For extremely long rails, the manufacturers generally recommend that the mechanical splice be connected at only one end. This allows for thermal expansion. When installing the electrical splice on spliced rails that require provisions for thermal expansion, install the WEEB Bonding Jumper with some slack in the tin-plated copper braid. Use one bonding jumper for each splice.