ESP Strap locks question

[Selfedge]

Hi guys!

I've recently bought ESP E-II Horizon NT HS, and it came with ESP ESL-01 strap locks.

When I was studying them I tightened the knurled nut without a strap, and now I can't loosen it back to put an actual strap in them.

Maybe this is stupid question, but these are my first strap locks, and I know that other manufacturers usualy have some bolts or openings for a screwdriver to untighten the knurled nut, but these strap locks don't have anything like that.

So, can someone who uses these strap locks help me with this question?

Thanks.

 

[cardinal]

This is the outer nut? I think there's a set screw on the side (small standard size); maybe you need to loosen that?

 

[Selfedge]

This is the outer nut? I think there's a set screw on the side (small standard size); maybe you need to loosen that?

Yes, it is the outer nut. On ESP straplocks there is no screw on the side of the nut unlike Shaller's S-Locks. As it is written in the description, they use so called "Perfect lock bolt" system, where two nuts have different thread lead angles and form a mechanical lock between them.
Maybe I just need something like ESP Multi Spanner Wrench to have more grip with the outer nut, or there is some trick with this system that i can't figure out.