The PCE-128 ISO / ASTM viscometer or ISO / ASTM Flow Cup Viscometer uses gravity to measure the flow rate of a liquid. Under ideal conditions, flow rate is proportional to kinematic viscosity. Thus, an ISO / ASTM cup is used to determine the kinematic viscosity of fluids. The structure of an ISO / ASTM Flow Cup Viscometer is standardized according to BS EN ISO 2431 / ASTM D5125. Designed for use with Newtonian and near-Newtonian liquids, this Flow Cup Viscometer series features:
- Orifice diameters (Ø) of 3 mm, 4 mm, 5 mm, 6 mm, or 8 mm / 0.12 in, 0.16 in, 0.20 in, 0.24 in, or 0.31 in
- Viscosity ranges of 7 ... 42, 34 ... 135, 91 ... 326, 188 ... 684 or 600 ... 2,000 cSt / mm²/s
- Flow times of 25 ... 150 or 30 ... 100 seconds (s)

The PCE-125 series Ford Flow Cup Viscometer uses gravity to measure the flow rate of a liquid. Under ideal conditions, flow rate is proportional to kinematic viscosity. Thus, a Ford cup is used to determine the kinematic viscosity of fluids. The structure of the Flow Cup Viscometer is standardized according to ASTM D1200 (Ford). This Flow Cup Viscometer series features:
- Orifice diameters (Ø inside) of 2.5 mm, 3.4 mm, 4.1 mm, or 5.2 mm / 0.10 in, 0.13 in, 0.16 in, or 0.20 in
- Viscosity ranges of 25 ... 120, 49 ... 220, 70 ... 370 or 215 ... 1,413 cSt / mm²/s
- Flow times of 40 ... 100, 25 ... 105 or 20 ... 105 seconds (s)