Universal Aluminum Billet Battery Tray Hold Down Relocation Box Mount OEM 551181. Overall dimensions of the base plate are 11.25″ length and 8.5″ width. It will fit batteries up to 10.5″ Length x 6.95″ width x 6.7″ height with provided thread sleeves(batteries over 7.4″ tall will require longer 3/8-16 all-thread). This battery tray is designed to securely mount your battery in your vehicle by using sturdy base plates and hold-down plates and includes heavy duty 3/8 hardware. Compatible with most car and truck batteries including the following Optima sizes: Red top 34 34R 34/78, Yellow Top D34 D34/78, Blue Top 34M D34M(may fit more batteries). They are made of aircraft grade alloy aluminum, hardened to be solid and durable, electroplated to be rust and corrosion resistance for long term service. OEM Part Number: 551181. Fitment Type: Direct Replacement. 1 x base plate, 1 x top plate 3 x all-thread hold downs with nuts 3 x thread sleeves. Please allow 1-3mm differs due to manual measurement. All trademarks are for identification and belong to their owners. Our close ties with KAKA bring exclusive deals and top service!