TOSIBOX SoftKey is a software-based access key. To use a Softkey you still require a Physical KEY. The Physical KEY is serialized with the LOCK. If you purchase a Softkey, then using the Physical KEY you can generate a SoftKey access code. The access code can be emailed or even text messaged to a remote engineer to gain access to the LOCK.
Like with a SubKey, you can revoke access to the SoftKey using the masterkey at anytime. This means you can grant a remote engineer access to a PLC for assistance, then revoke their access when they have completed the changes.