기능

• Screw that can be screwed and tightened at the same time
• The material of the high and low screw is special steel all-quenched, the high screw thread makes it easy to screw in, and the low screw thread provides unloosened tightening and strong holding force.
• It can be securely fastened without cracking or tearing, regardless of hard or soft materials such as gypsum board, nageshi board or plastic board.