The Kasco GI-M4 golf ball will help your game if; Symptom: ballooned drive; lack of iron shot maneuverability Effect: gain extra distance; make the shot more soild Suitable for; Competetive golfer with club head speeds of 120 MPH. The Kasco GI-M5 golf ball will help your game if; Symptom: short drive; inaccurate iron shot. Effect: gain extra distance; increase accuracy Suitable for; Average golfer with club head speeds of 100 MPH. The Kasco GI-M6 golf balls will help your game if; Symptom: lack of carry; weak trajectory. Effect: gain extra distance; easy to get the ball into the air. Suitable for; senior/lady/junior golfer with club head speeds of 80 MPH. 12 golf balls per pack. Availability: Usually ships the next business day. kascos$39.95 Choose ball model: GI-M4GI-M5GI-M6 *Specify Quantity after pressing "Add to Cart/Order"