The new ElectroRing Systems Stacker allows you to 'stack' ElectroRings together with 20mm spacing, but still maintaining the electrical isolation between each ring.
Add as many ElectroRings as you wish, the only limit is your imagination, and possibly the size of your penis.
You will need one 'Stacker' for every extra ElectroRing you wish to add.
The First two Rings will still require an ElectroRing Adaptor Pack, then after that you will need 1 stacker for each additional ring.