OTP key token generator ID card holder (to suit SafeNet OTP 110)

My employer recently introduced 2 factor login for our IT systems and issued SafeNet OTP 100 key generators to all staff.

These tend to get fastened to our lanyards (credit card sized ID Card Holders) - but they rattle when you move around and are a general nuisance.

I've designed this holder to fit the open syle ID card holders (as shown).

I printed with 0.15mm layers in PLA (added a small amount of support for the wider side of the recess), and it fits perfectly.