Disposable cuvettes are constructed of high-quality polymethyl methacrylate (PMMA or "acrylic") or polystyrene (PS), and are excellent for most spectrophotometry applications in the visible range Acrylic cuvettes are suitable for assays between 300nm and 900nm. Choose polystyrene cuvettes for routine assays between 340nm and 900nm. Cuvettes include an arrow mark to indicate direction of transmission and reduce variation. They are grouped by manufacturing mold cavity number to ensure the lowest variation in extinction coefficient, and are packaged in low dust, low scratch material. They provide accurate, reliable results and are available in macro and semi-macro sizes to accommodate most sample volumes. Cuvettes are compatible with most spectrophotometers and photometers.