(1) No waist measures: This type of swimming trunks has basically disappeared, because swimming trunks that have neither elastic bands nor ropes are easy to fall off, and it is not safe to walk, not to mention the impact of water waves after launching. Unless you have very close-fitting swimming trunks, you can take no measures, but for safety reasons, don't wear such swimming trunks.
(2) Only elastic band: There are many swimming trunks, but you must choose the tightness when you buy. Because the purchase is loose, it can't be tight anymore, and it is easy to fall. It’s tight, it’s not comfortable. But to remind everyone that the elastic band is prone to aging in the water for a long time, losing its elasticity and becoming loose.
(3) Only pants rope: the advantage is that it can adjust the tightness, and it is not easy to age like the elastic band, but this swimming trunk is rare, and it is almost eliminated, and there may still be disadvantages. However, most of the swimming trunks are like this.
(4) Both elastic and pants ropes can be said to be compatible with the nature of both, with the highest safety factor.