Painting the underside of a swim platform?

While I have the boat out (again), I'm contemplating painting the underside of the swim platform. Its looking pretty Sh***y. I'm not sure what type of coating was there originally, but I hit it with a sander today, and a lot of it was loose and flake off, while some of it was well adhered

S/V Pearl

SSTV 21-04 - Swim Platform/Bottom Paint/ Drying Out Your Boat

Painting the marine harbour, oil on canvas, Dubrovnik, Croatia

30 Underwater Paintings ideas underwater painting, swimming pools, pool

How To Add A Swim Platform And Ladder To Your Boat

Additional Boat Services

How to paint Non skid on aluminum swim platform

Fiberglass Core Material Fastening Tips

BUILD A SWIMMING RAFT: Download FREE Plans, Materials List, Instructions & Video

Hjdeck EVA Foam Boat Decking Camo Boat Flooring Mat Non Slip Marine Floor Carpet Self-Adhesive Sea Deck Boat Flooring DIY Trimmable Surfboard Traction Pad Kayak Yacht RV Flooring Swim Platform

Refinishing swim platform

How to Clean and Restore Teak Wood – TotalBoat