1. The head should be round (this is also the common standard for all round head screws). Because of the production process, the heads of drywall nails produced by many manufacturers may not be very round, and some are even slightly square. The problem is that it can’t be completely matched with the plasterboard after screwing in. Is it concentric circles and rotates around a point? This should be well understood.

　　2. The tip should be pointed, especially when you are using light steel keel. The sharp corners of drywall nails are generally required to be between 22 and 26 degrees, and the sharp corners of the head are required to be full without dragging and cracking. This "point" is important for drywall nails, because drywall nails are directly screwed in without pre-made holes, so the pointed tip also assumes the function of drilling through. Especially when it is used on light steel keels, bad points will lead to failure to drill and directly affect the use. According to national standards, wallboard nails must be able to penetrate 6mm iron plates within 1 second.

　　3. Don't be eccentric. The simple way to judge whether the drywall nail is eccentric is to put the round head down on the table to see if the threaded part is vertical and should be in the middle of the head. If the screw is eccentric, the problem is that the power tool will shake and wobble when it is screwed in. Shorter screws are fine, if longer screws run into this situation, it will be more troublesome.

　　4. The cross groove should be in the middle of the round head, otherwise it is the same as in 3.