Beaver Machine Corporation offers many different key numbers. Each key is constructed to fit Beaver machines exclusively. If you purchased your machine directly from Beaver, a key number will be on file and we request you contact Beaver directly. If the machine was bought through a third party you will need to confirm that the machine is a Beaver (Beaver will be written on the handle of the coin mechanism and on the lid) and the model. To identify the model of machine, please refer to our product catalog. Then, an A4000 replacement lock and key can be purchased to replace the unidentifiable old lost key.