Do you have a padlockable or key operated ball lock pin?

a padlockable pin would be equiped with a handle so that you could put your padlock around it.

a more easier solution is a key operated ball lock pin.

This smart block pin can be operated in the open position of the key, then you can acutate the push button to let the balls come into the shaft, so that the connection comes loose.

when closing the smart block pin with the key, you cannot actuate the push button, making it tamper proof for thieves

it's quite large, as you see on below pictures:

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