The average number of wire protection tubes in a box is more than 1 to about 1 grain. To replace a racket, on average, 2-10 new wire protection tubes need to be replaced, which means that at least 600-1000 rackets can be replaced in a box. When to change the protective tube? If you wait for the carbon of the racquet to collapse, and then expect to send a small protective tube to save lives, it seems a bit fantasy; if you can carefully inspect the protective tube before threading, once you find obvious deformation of the protective tube Or if it is damaged, then you should replace it with a new one by yourself or ask your threader to avoid unnecessary damage. Careful golfers usually replace most of the cable protection tubes before threading to prolong the life of the racket. Badminton racket grommet string frame replacement eyelet. One package includes single hole, double hole, you can choose the type you need. A small grommet will save your racket. Small size, easy to carry and use. - Durable, lightweight and long-lasting. - Small size, easy to carry and use. - Use these grommets to hold your rackets. - Durable, lightweight and long-lasting. - Small size, easy to carry and use. - Use these grommets to hold your rackets. - Model: Single wire hole Double wire hole Double nail - Quantity: more than 1600 - Colour: Black. - Material: Nylon. - Weight: 100-110g - Dimensions: Single wire hole diameter: 2.1 mm / Double wire hole diameter: 2.6 mm / The number behind the wire hole diameter is the length of the wire tube: such as 13.2, 7.9, 8.5... etc. are the length of the wire tube - Package: 1 box