This is an insert for adjusting the height of the arm on a Jaguar/Jazzmaster floating tremolo. For those who want to set the arm position higher. After installation, the arm is held by the strong magnetic force of the neodymium magnet, so it will not come off even if you turn the body upside down. Installation method Remove the tremolo block from the guitar and insert the neodymium magnet from the back of the arm holder (refer to the product photo). Adjust the position of the neodymium magnet to your liking, as the height of the arm will be determined by how far you insert it. Once the position is set, tighten it with the included tight lock and put it back in place. The height of the arm can be set from approximately 27mm or more from the tremolo block. Compatible with pop-in type floating tremolos on Fender Japan Jaguars and Jazzmasters, and arms with a diameter of 5mm. Although the brand is registered as Fender, it will fit other manufacturers if the arm diameter is 5mm and made of iron. Note The arm holder in the photo is for reference only. It is not included. The product includes one neodymium magnet and two tight locks, as shown in the third photo. Do not insert the neodymium magnet by hitting it with a hammer, as this may cause damage. Gently insert it after slightly widening the opening of the arm holder. Serious accidents have occurred where children have accidentally swallowed neodymium magnets and required abdominal surgery. This product is not intended for use by children, so it should be handled by those aged 14 and over.