This is a must for performance vehicles using the 2004R transmission. This drum eliminates the shaft breakage common at power levels over 300 foot pounds of torque.The production shaft is removed from the drum and replaced with a steel billet shaft welded in its place. This item has been tested in vehicles producing over 800 foot pounds of torque with absolutely no signs of distress. Fully CNC machined, shaped and ground. A core charge of $100.00 is included in the price of this product and will be refunded back to you as soon as you return the core drum to CK Performance 200-22 46th Avenue Bayside New York 11361 freight pre-payed, within 30 days of receipt of purchase. There are absolutely no exceptions. No core received within thirty days,no credit.