Pontoons are generally long, narrow flotation devices. They may be of box or cylindric construction, hollow, solid (i.e., concrete) or filled (i.e., with foam).
- May be lowered over the sides of heavy lift ships for additional buoyancy and stability while lifting
- May be used by cruise ships to aid embarking/disembarking to tenders
- Provide buoyancy to vessels or aircraft (float planes)