3 mm TEM grids with 600 nm holes in a 25 nm gold membrane supported by a 300-mesh grid of 10-12 um thick gold bars. The all-gold grid minimizes charging and drift, which can be especially important for cryo-EM applications.
Each grid square also has an amorphous region in the central 4 holes (marked by a gold dot) for Thon-ring-based calibrations, and the central grid square also has a single 10 um hole, through which a gain reference can be taken, as well as additional holes with amorphous films. Additionally, each grid square has a unique set of coordinate markers indicating where in the grid it is located.
