Used to mount the 90-degree rod holder on round posts. Align the 90-degree rod holder on top of the adapter plate at a 22 ½ 45, 67 ½ (found to be the best) or 90-degree angle according to the hole pattern in the adapter. Hold the adapter and 90-degree rod holder firmly together, and place the concave side of the adapter onto a round post. Place one of the (4) enclosed SS screws through an aligned hole in both parts and fasten snuggly into the post. Fasten the second screw opposite the first, then fasten the last two. Use the enclosed washers to prevent over-stressing the plastic. Do not over-tighten the screws, as this may stress crack the plastic. Product is warranted for 3 years after the date of purchase and will be replaced free of charge, if the product is proven to have manufacturing defects that caused failure, and has been used as a fishing rod holder under normal conditions. Proof of purchase required. Please allow 4 weeks turnaround time for a replacement.