Wilson Staff Di7 Distance Irons. New for 2007. Winner of of Golf Monthly's 2007 'Best on Test' Award. Wilson have developed their best game improvement irons - irons that will help golfers hit the ball longer and straighter than ever before. Deeper centre of gravity locations away from the face make the iron more stable on off-centre hits helping the player hit the ball straighter. Optimum placement of CG and proportioned sole width makes the Wilson Di7 Distance irons the most playable wide sole iron on the market.