As a traditional helix coil machine, the RDS is the least expensive of all vending machines and it can only issue items out. No returns to inventory are possible. A helix coil machine is great if you have just a few item types that you want to dispense, and you want to dispense a large quantity of each item. The helix coil can hold only 60-70 different item types because the machines are limited by the number of coils in the machine. You can get the machine configured with 6 or 7 rows with each row holding 10 coils thus limiting the number of different items to 70. Each coil can hold from 4 to 40 of the same item depending on thickness. If your application is to dispense a high quantity of items but you don’t have much diversity of items, the helix coil may be for you. Our experience shows that most applications today require almost the exact opposite so let’s look at a machine designed with an entirely different purpose.