The SPI Supplies Division of Structure Probe, Inc. is now known worldwide as a leading manufacturer and distributor of sample preparation equipment and consumable supply items for the routine operation of the typical SEM, TEM, LM, SPM and surface analysis laboratory.

They are also known as the innovator in the corner of the microscopy and microanalysis market, being the first to bring to commercial realization now familiar products such as colloidal gold probes and silicon nitride membrane window grids.