BlueROV2 Machined Buoyancy Foam

LAST-A-FOAM® R-3318 is a machinable, hydrostatic pressure-resistant foam that provides buoyancy underwater. The closed-cell structure is engineered to resist penetration by water. Due to its pressure resistance to many fluids and resins, it is also used in resin-transfer molding as a core material. LAST-A-FOAM® R-3318 semi-submersible foam is optimal for shallow to mid-water underwater robotics applications.
This particular size is machined to fit perfectly into the BlueROV2 fairing and maximize the amount of available buoyancy. Upgrading to this machine foam adds a total of 500 grams (1 lb) of additional buoyancy. This adds more stability and payload capacity to the ROV.
here-->Rated to 300 meters operation depth when uncoated.
Features

Easy to machine, coat, and paint
Excellent compressive and insulation properties
Resistant to hydrostatic pressure
High impact resistance
Biologically Inert
Oil, grease, and solvent resistant
Cost-effective solution
Does not rot or decay
Performs in freshwater or saltwater
Compatible with many types of adhesive