This battery cage is designed for mounting 4s LiPos on 10mm rails with 60mm centers. The end mounts are designed to have velcro straps attached to stop the battery moving backwards or forwards and there is a small gap on the internal sides and bottom to attach some form of padding if you want, however I've found that the velcro end straps hold the battery pretty central on their own. While light (each one I've made comes in at around 12-14g per mount in PLA), the cage is strong enough to offer some good protection to the battery in the event of a crash and you can make as many inner mounts as you like to spread the load or offer better protection. The Tarot zyx LED mount visible on the bottom is not included, but if you want the file contact me.