This is a set of 28 used hard tennis balls (all Dunlop Fort). 【Dunlop Fort】 This ball is the most widely approved ball in Japanese hard tennis tournaments. It feels great when hit and is very popular, but the price is high, with new balls costing around 550 yen for two at the lowest price. I have used these balls for 3-4 hours on weekends for matches and practice since about a month ago. There may be slight differences in air pressure depending on the ball, and some balls have marks or other identifiers to distinguish them from others. However, there is almost no wear on the logos, and they are in good condition, so I think they can still be used for practice, etc.