※ Please carefully measure the ring size of your guide. If the size is different, you won't be able to install it. If you can confirm the guide's model number, you'll know the required size. We offer rings in 4mm, 5mm, 5.5mm, 6mm, 7mm, 8mm, 10mm, and 12mm sizes, so if you're looking for a different size, please search from the list of our products. These are SiC (Silicon Carbide) rings. Please use them to repair broken guides. They can be installed on guides with a frame ring contact surface diameter of 8mm. Here's how to install them: 1. Prepare the guide frame. Pre-sand and clean the ring contact surface of the frame. 2. As shown in the third photo, place the ring vertically and try to pass it through to the other side. It's ideal if it goes through with a little pressure. If it doesn't go through, use a file to shave the frame and widen the contact surface. 3. Insert the ring into the frame. If it's tight, gently crush it with protected pliers to fit it in. (Photo 4) 4. Apply adhesive to the border between the ring and the frame. Epoxy adhesive with some time to work with is more suitable than instant adhesive. Apply the adhesive to the tip of a needle or toothpick, and trace the outer circumference of the ring, applying it to both the back and front surfaces. A thin layer of adhesive is sufficient. Be careful as the ring can break if it receives a strong impact. When it breaks, it breaks cleanly with a crack, so be careful when inserting it with pliers. It comes in a set of 3 for when you make a mistake. Although the adhesive strength will be lower, it's also an option to shave the frame more and fit it loosely. If you use epoxy adhesive, it won't come off easily, so you don't need to strive for perfection. If you do it well, you can convert inexpensive guides to SiC guides. If you're interested, please give it a try. This is a special product, so please ask if you have any questions.