As seen on the ledger, the customer ordered it at 4.5kg max.
That's were it's at.
One can also see that the delivery was supposed to be March 30th, and they missed that as the gun was still worked on in April. However, it started in February, so that's not too shabby!
One could wait many years for a gun like this nowadays.

Here are the catalog pages:

The 9/40 model explains the 2nd column in the ledger.

Best regards,
WC-