The plates are very easy to install and remove and do not require any additional tools. To remove the lower or upper interchangeable plate, push the corresponding slide button on the locking mechanism forward until the respective plate is unlocked. Carefully lift and remove the unlocked interchangeable plate. To insert the lower or upper interchangeable plate, position both retaining pins of the respective plate in the openings provided on the device. Once the plate is correctly positioned, press the plate down or up until it audibly clicks into place.