This is a socket installation tool used when assembling or reshafting golf clubs to insert the socket onto the shaft and install it in the correct position. Product Specifications: Material: Steel plating Length: Approximately 85mm (minimum) to 124mm (maximum) Outer Diameter: Approximately 21.4mm Weight: Approximately 177g Inner Diameter of Shaft Insertion Hole: Approximately 10.5mm Depth of Shaft Insertion Hole: Adjustable from approximately 17mm (minimum) to 56mm (maximum) Loosening Prevention: Spring washer This product is my original development with four features: ① Compatible with various shaft specifications with just one tool ② Stable installation with a durable, one-piece construction ③ Loosening prevention with a durable spring washer (Ver. 1) ④ Ingenious design for smooth screw movement Feature ① Applicable to both steel and carbon shafts for all club types, from drivers to wedges. The socket installation depth varies depending on the head, but is generally around 25mm to 40mm. With this single jig, the depth adjustment of the jig bolt allows for adjustment to accommodate all club assemblies. Feature ② As shown in image 1, the socket is hammered into the designated position from above. The durable, one-piece construction allows for stable socket installation. When actually attaching the head, adhesive is used, so I think a tip is to set the depth about 0.3-0.5mm shallower. Feature ③ As shown in image 6, a spring washer is inserted to prevent screw loosening. From my experience, this is effective when the socket is tight and the number of hammer strikes is high. The spring washer is made of metal, so it is durable and suitable for outdoor use. Feature ④ To make depth adjustment easier, the bolt screw is designed for smooth movement. (The ingenuity is a trade secret and not disclosed.) For socket installation methods, the work of craftsmen on YouTube channels like "How to Make Golf Clubs" and "Today's Reshafting" is helpful. ※ Many people have purchased this product, and I have used it without any problems, but please use it at your own risk. ※ The product for sale is shown in the second photo. ※ Please read the profile section.