Check the listing for details. TRAXXAS SLEDGE Compatible TALL BATTERY EXPANSION MOD Up to 47, 48, 0r 50mm HIGH. Color: Black, Condition: New. Listed at 9.99 USD. This is a kit that raises the allowed height in the stock battery tray on the TRAXXAS SLEDGE.The stock 45mm height can be raised to 47mm, 48mm, or 50mm with included spacers.No permanent modification to car required.Easy to install.Auction includes 4 spacers (2 x 2mm, 2 x 3mm) and all required hardware. Check out the ReactionRC store for other upgrades and discounts. Installation:Remove battery tray from car. Remove the 4 screws holding the 2 side towers down and remove them from battery tray. Place spacers where the side towers were removed to raise to the desired height (2mm, 3mm, or both for 5mm). Fasten the side towers back down with the included 20mm screws (don't forget to put the top battery hold downback in place) and reassemble car. This is a custom ReactionRC part and not associated with TRAXXAS.