 In the United Kingdom single-ply sheets of veneer were used to make stove pipe hats in Victorian times, so flexible modern plywood is sometimes known there as "hatters ply", although the original material was not strictly plywood, but a single sheet of veneer.Marine plywood is manufactured from durable face and core veneers, with few defects so it performs longer in both humid and wet conditions and resists delaminating and fungal attack.Its construction is such that it can be used in environments where it is exposed to moisture for long periods.