Update: posted my Otter Mercator yesterday, today I got a Kwik Stud and modified it to work better for this slim knife. Here are some pics of the finished product, and explanation

Messer Mercator Stainless OTT10826R_AB : Sports & Outdoors

Mercator Black Cat Carbon Knife : Sports & Outdoors

OTTER-Messer from Urban Kit Supply

Kwik Thumb Stud - Brass : Tools & Home Improvement

1924us Mercator - Solid Brass

A true masterpiece Amongst Cult Knives- Otter Mercator Black Cat

BSB exclusive review of Otter Messer Mercator by Old School EDC.

Mercator by Otter-Messer Traditional German Folding Pocket Knife – Top Shelf Worldwide

Otter - Messer Mercator Brass Large Carbon : Sports & Outdoors

USA Knifemaker Supply Kwik Thumb Stud Black Oxide

OTTER-Messer Mercator Folding Knife 3.5 Carbon Steel Blade Stainless Handle