1) Embedded screws are mainly used for suspending and fixing air-conditioning pipes, water pipes, electric pipes, ceilings, etc.

(2) Torsion flat-head non-standard screws can be used on cement concrete, brick walls and hollow bricks, etc., for fixing sanitary equipment.

(3) Internally forced non-standard screws with internal teeth are used for fixing marbles, water pipes, electric pipes and angle irons.

(4) Sleeve-type non-standard screws are mainly used for fixing soundproof walls and sanitary equipment.

(5) Externally forced internal thread non-standard screws, mainly used for hanging and piping of water pipes, electric pipes, and air conditioners, as well as fixing various angle irons and section steels.

(6) Non-standard screws for torsion casing are used to fix lighting, light steel dragon skeletons and sanitary equipment.

(7) Hollow non-standard screws, suitable for fixing door frames, cabinet frames, bathroom accessories and wall decorations.