CalibrexTM universal 520 Bottle-top dispensers Three colour-coded models with adjustable volumes are ranging 0.25 to 2 mL, 1 to 5 mL and 1 to 10 mL. The CalibrexTM combine a clever, yet simple construction and a universal chemical compatibility. Among other features, they are particularly appreciated for their smooth, effort- less activation and their sturdiness. Base thread fits 32 mm bottle neck diameter. Each 520 models comes along with 3 adapters (PP material) for 28, 40 and 45 mm bottle neck diameters. See bottle-neck adapters for additional sizes and materials. CalibrexTM universal 520 Fixed volume bottle-top dispensers Fixed versions also available in any volume within dispenser range. Supplied with same bottle neck adapters as above.