Details:* Machined with external marking points, used to accurately align inventory for proper placement of studs or tenons.* Dowel centers made of carbon steel so you can use it on hardwoods as well as softwoods.* Fixed dowels and you can choose the ones you need * Just drill one set of holes, slide the dowel centers in and press the joint together.* Points on the dowel centers accurately mark the locations of the holes on the other item.* Color: Black (as pictures show) * Material: A3 carbon steel * Size: 6mm, 8mm, 10mm, 12mm (approx.), 2 pieces for each size * Quantity: 8 pieces Use steps:1. After the wooden tenon is connected to the wooden block, the wood round tenons is covered with a wooden tenon2. Align the top of the head with another block of wood that needs to be cut3. Thus, on the second block of wood there is a sign of a round head4. Use a drill bit to drill a round head, then the two pieces of wood are perfectly connected without dislocation and tenon Package Contents:8 * Expansion PlugNote:1. The actual colors of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness.2. Please allow slight manual measurement deviation for the data.