A drill includes a center insert which is indexable, mounted in a center pocket, and has an elongate basic shape. A tightening percentage may be 4 to 11%. The locking mechanism may include a hard stop which is selectively movable into position to block retracting movement of the slit valve door. A dielectric layer, which is formed from tungsten oxide, serves as a capacitor dielectric. Payouts to the player are based on the final outcome and whether the player has made payment.