Free - Twin Disc MG-506 Troubleshooting Guide Twin Disc MG 506 Marine Transmission Parts - Transmission Ring Set Section Loading... 1 Twin Disc Ring set for MG506 marine transmission . Price: $ 157.48 Qty: ^ Details In Stock Add to Cart 2 Mechanical & Electric Gauges See Our Gauges Page 3 Controls Cables & More... See All Control, Cables & More 4 Marine Water Pumps See All Marine Water Pumps 5 Fresh Water Pumps See All Fresh Water Pumps Free - Twin Disc MG-506 Troubleshooting Guide