Monoblock Flexi Connectors

Hi. I'm refurbishing my utility room and fitting new worktop and sink/drainer.
Thought I'd use flexi tube this time so bought a pair of 15mm steel braided 10mm tap fit.
The pair are overall the same length but one of them has a 20mm steel end whilst the other has just the finished crimped end.
Can anyone please tell me why they have this difference.

arryB

To make fitting easier.
Fit the one without the stem first.

Don't over tighten them.