Only used once for testing after purchasing new. This is a non-slip grip aid for golf and tennis. 【Innovative Technology】By utilizing Chalkless's unique patented technology, we have succeeded in developing an innovative non-slip grip aid unlike any other, by combining lipophilicity (the property of absorbing oil) and hydrophobicity (the property of repelling water), which are opposing properties. This novel combination takes grip strength to a higher level. 【Monster Powder】Chalkless's amazing grip strength is created by the granular powder, Monster Powder. It absorbs sebum on the skin's surface, which causes slippage, and then repels sweat and water. Rubbing it on the hands or the surface of a golf grip provides a strong and long-lasting grip. 【Overwhelming Durability】Rubbing Monster Powder on the surface of the hands forms a very thin coating (film). This coating repels moisture such as sweat, allowing grip strength to last for a long time. 【Instant Effect in 3 Seconds】It works the moment you apply it to your hands. Also, there is no need to wait for it to dry like liquid chalk. Chalkless maximizes its effect from the moment it is applied to your hands. 【Golf Information】Approved by the USGA, so it can be used in competitions and matches. Regarding the R&A, it can also be used in R&A competitions and matches because of the cross-licensing agreement with the USGA. *Confirmed with the JGA as well. Golf Tennis Non-slip grip