Nylon Backstroke Flags - 45 Ft. (Pair) (Black+Yellow) Nylon backstroke flags are for use in both indoor and outdoor pools. Kiefer nylon backstroke flags are 12" wide x 18" high, prestrung on white nylon tape with a 12" gap between flags. 10 feet of extra tape is provided on each side for attachment to backstroke stanchions. Includes two 45' strands.