In reply to kingjam:
Any knot that is correctly tied. DF ideal.
Two of everything to provide redundancy.
Metal, krab or maillon, to ease rope retrieval and reduce wear.
Continuous loops of rope rather than tied in to bolt/ thread so the full length of the cord can be visually inspected for wear ( or eating by mice !! ). It also evens out wear points.
Never understood the rational behind static rope. The short lengths involved mean stretch is minimal and climbing rope knots so much more securely. Retired climbing rope is fine if the sheath is in reasonable condition.