Thomas Stainless Steel Zahn Signature Viscosity Cup, #2 Size, 39 to 238 Poise Centistokes Dip viscosity cup stand for Zahn Cups Calibrated with Cannon viscosity standards traceable to NIST; Cannon standards are produced in accordance with ISO 90002 Looped handle and finger ring Made of polished stainless steel 39 to 238 poise centistokes range