Wilson Slam JR 25 Boys TNS RKT 3 7/8″ tennis racket. The Wilson children’s racket is suitable for recreational tennis matches. AirLite Alloy technology creates a lightweight and durable construction. Aluminum construction. Technical data: Age: 8/10 years or height 135-150 cm. Grip size: L0 (3 7/8). Material: aluminum. Racket weight (unstrung): 205 g. Racket length: 63.5 cm – 25″. String pattern: 16×19 in. Balance: 30 cm. Head size: 683 cm² / 106 in². Factory grip: yes. Factory stringing: yes.