Free - Twin Disc MG-506 Troubleshooting Guide Twin Disc MG 506 Marine Transmission Parts - Ring Gear & Rubber Blocks Section Loading... 1 Twin Disc MG506, MG507 & MG507-1 Ring Drive Housing size SAE #2 Price: $ 754.83 Qty: ^ Details In Stock Add to Cart 2 Rubber block for Twin Disc marine gears . Price: $ 6.03 Qty: ^ Pictures In Stock Add to Cart Go Back Free - Twin Disc MG-506 Troubleshooting Guide