Some cots are equipped with small wheels that can be pushed and pushed freely. This kind of small bed must pay attention to whether it can be installed with brakes, and the small bed with brake installation is safe. At the same time, the brake installation should be firmer and not loose. There are also small beds that can be shaken and have the effect of a cradle. This bed must also pay attention to whether the connection of its parts can be tight and secure. It is best not to buy a small bed that can only be shaken and can not be fixed. Because the baby grows fast, the time to sleep the cradle is short, and the demand is still a fixed bed.