Is the stainless steel guardrail on the swimming pool made of expansion screws?

The installation method of expansion screw is not difficult, and the specific operation is as follows; First, choose an alloy drill with the same diameter as the expansion ring (tube) of the expansion screw, install it on the electric drill, and then punch the wall. The depth of the hole is preferably the same as the length of the bolt, and then the expansion screw set is lowered into the hole together, remember; When the hole is drilled deep and difficult to take out, do not unscrew the screw to prevent the bolt from falling into the hole. Then, tighten the nut 2-3 times, and then unscrew the nut after feeling that the expansion bolt is tight but not loose. Then, install the fixing piece with the hole on the fixed object on the positioning bolt, and install the outer washer or spring washer to tighten the nut.