3M™ Marine Adhesive Sealant 5200 Black.
 The adhesive sealant is extremely strong, retains its strength above or below water line. Stays flexible too - allows for structural movement. Has excellent resistance to weathering and salt water.                                         
      - High performance polyurethane adhesive/sealant becomes tack-free in 48 hours, cures completely in 5-7 days
     - Strong seal retains strength above or below the water line
     - Excellent resistence to weathering and saltwater
     - Marine, general industrial
     - Bonding, attaching, and assembling