Features: This is a woofer voice coil positioning gauge and also a woofer voice coil repair parts. It can be used for speaker woofer voice coil maintenance. Non-disposable product, can be used repeatedly. Each batch is different, the color is different, does not affect the use. Check the size carefully, if the size does not match, the buyer will bear the return shipping cost. Magnetic circuit gauge, voice coil gauge, magnet gauge, the three products are different and cannot be used interchangeably. Note:Color Random. Specifications: Material:ABS Size:19mm / 25mm/35mm/38mm/50mm/65mm/75mm/100mm/13mm/14mm Option Type:Type A;Type B;Type C;Type D;Type E;Type F;Type G;Type H;Type I;Type J;Type K;Type L;Type for M;Type N;Type O;Type P; Package Includes: 1x Speaker Voice Coil Positioning Gauge(Color Random) note: Please allow 1-2cm errors due to manual measurement,pls make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.