Flat nylon webbing is great for high abrasion applications, or for use with larger buckles with higher breaking strengths. 

It is ideally suited for leashes, collars, leads, ratchet straps, D-ring belts, etc. If you need a heavy duty strap to hold down a large item or multiple items, pair this webbing with a ratchet or cam buckle, and you have a monster strap.  Nylon webbing is not particularly good in applications around water because it stretches about 2% over time,when it gets wet. So a nylon strap will not stay tight in the rain or on a river trip. However, it is very colorful and available in 5 different sizes.