These balls feature excellent durability and consistent playability

as the sponge

Full-length closed-cell foam supports and cushions the foot for long-lasting comfort and responsiveness

Interaction between layers absorbs friction

turn to Ashaway Crossfire II tennis string

Ashaway Crossfire 18 COLLECTION-Type-Stencils and Ink These balls feature excellent durabilityFor maximum playability and superior durability, turn to Ashaway Crossfire II tennis string. Hybrid technology provides resilience, ball control, and optimum spin. Recommended for chronic string breakers and top spin players. Main strings: 18 gauge 100% aramid fibers bonded together with nylon resin. Cross strings: 16 gauge synthetic gut with abrasion resistant wear layer. Use 10 15% less tension on Aramid mains than on Synthetic Gut crosses.