NEW GM 8.5" 10-Bolt TA Performance Aluminum Rearend Girdle Cover TA-1807 All TA Girdles are made of 356 aircraft grade aluminum, heat treated to T6 specifications, each cover is then stress relieved. All Girdles incorporate a Fill Port and a Drain Port for ease of servicing. All Girdles incorporate 2 load bolts with swivel "feet" for supporting the bearing caps. All Girdles increase fluid capacity approx. 1/2 pint. All Girdles show a decrease in operating temperature, average of 15 degrees.