Drop Slot Safes, Constitution Safes & More The main purpose of a depository safe is to protect money or documents for a limited period of time. Before you choose a depository safe you should consider which type will best benefit your company. Many of the safes range in size or shape and a variety are sold with easy to use digital locks. Larger depository safes or cash safes are generally found in restaurant or retail offices so daily drops can be made easily. At the end of a shift, a manager can account for and then bring the money for deposit in the commercial bank. Smaller deposit boxes are suitable for limited spaces under the register and commonly are a safe option for bills over the $20 limit.