Back before wire ties, cables were bundled with lacing cord — a flat or round waxed nylon string (flat vs. round require different knots). To this day, lacing cord is used in certain situations where a more flexible bundle is needed, when wire ties are too bulky, or when you need to pull another cable alongside and the lumps of the wire tie would cause problems. Depending on the job, lacing cord comes in a variety of different coatings, materials, strengths and lengths.
Other advantages of lacing cord are that it’s cheap; there isn’t a specific size (cut to any length needed); and it’s good strong cordage that can be used for other things. The main disadvantage is that it takes a bit of skill with knots. You have to be able to tie a clove hitch for the flat cord, or make a slip knot for the round ’12 cord’ and then finish with a half-hitch knot.
I’ve been using lacing cord for over 20 years. As for brands, one brand is pretty much the same as another.