I want to hang a hammock on the balcony, the wall thickness is about 400, I see that the ordinary ex

First of all, see if your wall is hollow, if it is hollow, you need to buy the expansion bolts that are special for special hollow bricks. This expansion bolt tightens the hollow brick and then tightens the thread hard, which will expand a piece of iron similar to a beam at the head, which can better expand into the hollow brick.

However, it is recommended that you do not buy ordinary expansion bolts, it is recommended that you buy expansion hooks, which are basically the same as ordinary expansion bolts, but at the front end is a hook, which is specially used to hang things, such as ceiling fans, etc.!

If it's just a hanging bed, just an adult lying on it, just use the M10 expansion hook, even if that adult weighs 100KG, I don't think there is any problem!

This kind of expansion hook is generally sold in hardware stores, and the price does not have to be much more expensive than ordinary expansion bolts.

There are lengthened wall screws, if it is a concrete wall with 10 cm, the brick wall is not easy to say, how long the brick joint is in vain, not to hit a wall, safe.

The wall should be solid, so that the screws will not fall off.