Most Mason jar lids are made of tinplated steel, which rusts quickly and easily. Here at the Mason Jar Lifestyle we always try to source the highest quality items, and this tooth brush lid is stainless steel!
Each of the 4 holes are 1″ in diameter.
They are made of 18/8 304 grade stainless steel, which is resistant to corrosion and rust. However, even stainless steel can rust eventually if it is constantly wet.