Read a rope label
Separate fiber, construction, and length per piece.
Start with the package quantity
A twin pack can list a length per piece or a total for the package. If it only gives one measurement, confirm which it means. Keep the original label with the rope so the fiber and care instructions stay identifiable.
Record what the label does say
Fiber, diameter and construction are separate specs. A silky finish does not identify the fiber. A nylon rope can also differ in construction and end finish from another nylon rope.
Inspect the ends
Check for a separating cap or damaged fibers when unpacking. Set damaged pieces aside. A marketing description of strength is not a load rating; these listings are not guidance for suspension.