External Hex Expansion Bolt

External Hex Expansion Bolt ：Put expansion screw and expansion pipe into wall together, and then lock the nut. When the nut is locked inward, the screw will pull outward, and then open iron expansion pipe and card it into the wall to play a firm fixed role.

Plastic Anchor Screw：The plastic expansion pipe needs to put expansion pipe into the hole, and then screw into expansion pipe. The step is slightly more troublesome, but the principle is similar.

The price is different, metal expansion bolt is more expensive than the plastic, a metal can buy about 20 plastic;

Plastic models are relatively few, M6-M14 mostly, but metal has M6-M24 size.

The bearing force is different, bearing force of metal is much stronger than plastic.Metals are used in many scenarios, such as anti-theft net / doors and Windows fixed, and plastic is mostly used for household frame / curtain rod / small lamps and lanterns installation.