I am selling 100cc of needle hole repair liquid. 0.8-1mL of repair liquid is recommended for one ball. Over 100 balls can be restored. Let's restore deflated balls instead of throwing them away! Throwing them away is trash, using them is a resource! The restored balls can be used immediately after the repair liquid dries. In most cases, the balls will be revived in about 1-2 days (since air is injected for restoration, the felt part will not return to its original state)! The following necessary items for tennis ball restoration are sold separately: Ball needle and silicone tube included (The needle is cut short and the tip is processed to make it less likely to bend and clog.) It is easier to insert and remove the needle, and the life of the needle will be extended if you wet the needle with water before inserting it into the ball each time. A silicone tube is attached to the pump to prevent air leaks. Ball repair liquid injector (syringe) If the rubber of the syringe becomes hard and difficult to move after long use, you can use it for a long time by occasionally applying a little grease. Ball clamp: Prevents the hole until the repair liquid dries and can also stand on its own. Color cannot be specified. *Any standard Schrader valve compatible bicycle pump can be used. A pump with a gauge is recommended. The air pressure of a new ball is about 1.8 psi, but sometimes there is an air leak, so I inflate it to about 2 psi for restoration and then wait for a few days until the repair liquid is completely dry before using it. The method of restoring the ball is not to remove the needle once you have inserted it until the work is finished. 1) Wet the needle with water and insert it into the ball to release the air pressure. 2) Inject the repair liquid. 3) Connect to the pump and inflate to 1.8-2.0 PSI air pressure. 4) Slowly remove the needle and prevent the hole with a ball clamp, store it with the hole facing down for a few days, and it's done! Type...Pressure ball Use...Hardball