24 Well Assay Plate, Polystyrene, Clear Bottom, Black, 24 Wells, ANSI/SLAS Standard Base and Footprint, Black Opaque Wells, 68 Assay Plates per Case. This assay microplate is for optical and luminescent assays. Format - 24 wells, ANSI/SLAS standard base and footprint. Bottom - Clear. Material - Polystyrene. Color - Black opaque wells. Supplied by Arctic White as 68 assay plates per case.