Dunlop St. James tennis balls, made of nylon and wool, pressure-packed, pack of 4. - Brand: Dunlop - Model Name: St. James - Quantity: Pack of 4 - Material: Nylon and wool - Pressure: Pressure-packed My child bought these for their first time playing hard court tennis, but they switched to soft tennis soon after, so I'm selling these! They are new and unused, but there may be some signs of storage. Thank you for looking!