What is the difference between Over Platform Boat Ladders, Under Platform Boat Ladders and Rope Grab Ladders?

Over and under platform boat ladders are similar in design with a few key differences.

Under platform boat ladders mount underneath your swim platform, seperating hardware from usable surfaces. They sit recessed into shelves/compartments when not in use, and slide out from your boat and telescope into the water at a depth determined by the number of rungs.

Over platform boat ladders rest on top of your swim platform, folded and retracted into place. They have gudgeons to separate the hardware from your deck to prevent surface damage. Instead of sliding out of a compartment, they fold out over the water, and then telescope downward for use.

Rope grab boat ladders are manually mounted/dismounted from boat tie-offs (or any weight-bearing anchor point), and stored in a bag or compartment when not in-use. Because they are not permanently attached to the hull/platform, they can be used to enter/exit your boat from any side. Generally rope grab ladders are the easiest and least expensive option for your boat.