Rear Mount Composite Rod Holder for Cannon Downrigger Cannon Rear Mount Composite Rod Holder Single downrigger-mounted rod holder features dual axis adjustability. Perfect as a spare, replacement, or adding additional rod holder to Tournament Series downriggers. PART 1907070 Features: Dual axis adjustability. Original equipment replacement for downrigger mounted rod holders. Includes necessary hardware. Cannon composite rod holders mount directly to your downrigger or boat and come standard on several models.