Hi Einstein,
I would suggest just a little caution with unusual (Krone) IDC insertion tools.
The jaw width on each terminal is critical as it must be just the right size to "bight" through the wire insulation.
If you force the terminal apart it could widen the jaws so that an intermittent connection is produced.
EDIT I've attached a close up picture of the approved Krone insertion tool. You can see that the gap ensures nothing interferes with the jaws of the terminal, whereas your credit card might force the jaws apart.
Chasing intermittent problems can be the very devil to eliminate and you could end up spending a lot of effort costing far more than the price of the correct tool.
Kind regards,
Walter
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