Pretty self explanatory: a mod that allows you to lock slots so that items in select slots can not be moved/dropped until the slot is unlocked.
Same concept as the slot locking feature that sba had and neu has for skyblock except this is for general usage, whether you’re playing in a survival world, pvping, or whatever you might need it for.
Very helpful to prevent accidentallñy dropping valuables or putting them in the wrong places.