This is a universal cap holder for 77mm lens. It is remixed from various fantastic designs already available on TG and designed to be attached to PEAK DESIGN neck strap (SL-2 model)
Compared to other versions, it is thinner (only accept 77mm diam cap) and larger to fit PEAK DESIGN strap. Edges are also rounded to preserve the strap from scratches and friction damages.
Feel free to comment, print it as it is or create your own variation.