The inside corner with a 3" pipe holder replaces the standard inside corner (H-IC) and creates a place for you to use a 2-1/2" ID pipe (or less) to anchor your dock in place. With an inside corner pipe holder no anchoring hardware protrudes on the outside of your dock. When you use this hardware you will need to cut out a hole in your decking and you will also need to think about where your floats are located (if you are using floats). Use with 1/2" carriage bolts. PDF Drawing