I worked in the shipping department in the garment industry. A box cutter was a necessary instrument to carry. I made this to identify mine. I followed a pattern for a manila boat fender using 3 strands of cord. I retired after having used it for several years and I still keep it attached to the box cutter. It is a bit ratty but still functional. The Matthew Walker Knot that I used to finish the fob was tot tied tightly enough and came loose. I modified the MWK and buried the ends in the fob .