Whenever your job calls for securing round flexible duct to outlets, pipes or fittings, you can do the job better, faster, and at a lower cost using DYN-O-TIES, flexible duct ties. No tapes, no screws, no clamps. Position the flexible duct and slip a DYN-O-TIE around the flexible duct over the joint. Draw the DYN-O-TIE tight with the ratchet action hand tool. A push with the thumb completes the job by clipping off the excess nylon tab for the neatest and most secure connection you could want. Duro Dyne UV DYN-O-TIES are made to resist Ultraviolet rays and adverse weather conditions when used in outdoor applications. DYN-O-TIES, when properly installed, provide a secure connection of flexible duct listed by Underwriters Laboratories Inc., class 1. Dyn-o-Ties are tested to CSA C22.2NO.18.5-02 / UL 1565.