
Calibration Weights
Accurate and stable reference standards for calibrating weighing equipment, including variously certified/accredited weights and weight sets from different classes. Products may be constructed of aluminum, stainless steel, brass, iron, and other alloys.
Calibration weights (also known as reference weights or test weights) are manufactured to meet high tolerances and accuracy. They are used to spot-check the performance and verify the calibration of analytical balances, precision balances, and general-purpose scales in research laboratories, educational settings, and other working environments. Some calibration weights may also be used as reference weights for the calibration of improvised or non-certified weights.
How Are Calibration Weights Made?
Calibration weights may be take the form of simple discs, cylinders, wires, or leaves. Sold separately or as sets, they may also be supplied with tweezers, gloves, and a protective case. Calibration weights are often supplied as accessories for specific balance brands and models.
Calibration weights are made from polished brass, aluminum, special stainless steels, or other metals for durability, anti-magnetization, and resistance to corrosion or wear that may affect their accuracy.
Available in nominal values from a few milligrams to 10 kg or more, they may be supplied with certificates or statements of accuracy, compliance, and traceability.
How Are Calibration Weights Classified?
Calibration weights are classified based on accuracy by organizations such as ASTM, OIML, and NIST. The appropriate classification depends on the resolution of the balance and the degree of accuracy needed to satisfy a particular weighing application.
Principal Classes of Calibration Weights:
• Class M1: For standard scales
• Class F1: For precision electronic balances
• Class E2: For highly accurate analytical balances
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Product Type | Calibration Weight |
---|---|
Classification | ASTM Class 1 |
Packaging Quantity | 1 |
Quantity | Each |
Material | Stainless Steel |
Includes | Plastic box |
---|---|
Shape | Cylindrical |
Product Type | Adjustable Cavity Weight with Knob |
Classification | OIML Class F1 |
Packaging Quantity | 1 |
Quantity | Each |
Material | Stainless Steel |
Certifications/Compliance | ISO17025:2005, ISO9001, ISO14001 environmental standard |
Density | 7.9kg/dm3 at 20°C |
Troemnerâ„¢ Individual Analytical Precision Weights, Class 1 with Traceable Certificate
Designed for your most demanding weighing applications
Includes | Polycarbonate case |
---|---|
Classification | ASTM Class 1 |
Quantity | Each |
Certifications/Compliance | Traceable certificate, ISO9001 |
Mettler Toledoâ„¢ Analytical Individual Weights: ASTMâ„¢ Class 1
Low magnetic permeability and high corrosion resistance for reliable stable values
Classification | ASTM Class 1 |
---|---|
Packaging Quantity | 1 |
Quantity | Each |
Material | Stainless Steel |
Density | 7.9kg/dm3 at 20°C |
Mettler Toledoâ„¢ M1 OIML Class Advanced Weight (M1 PL C E)
Single M1 OIML weight includes a calibration certificate and is housed in a plastic box.
Includes | With certificate |
---|---|
Product Type | Test Weight |
Material | Stainless Steel |
Case Material | Plastic |
Density | 7950 (± 140) kg/m3 |
Mettler Toledoâ„¢ Analytical Individual Weights: ASTMâ„¢ Class 3, With Calibration Certificate
Low magnetic permeability and high corrosion resistance for reliable stable values. Supplied with a calibration certificate.
Includes | Plastic box |
---|---|
Classification | ASTM Class 3 |
Packaging Quantity | 1 |
Quantity | Each |
Material | Stainless Steel |
Certifications/Compliance | With certificate, ISO17025:2005, ISO9001, ISO14001 environmental standard |
Density | 7.9kg/dm3 at 20°C |
Sartorius Individual Precise Calibration Weight
ASTM Class 1 Individual Precise Calibration Weight without Certificate.
Product Type | Calibration Mass |
---|---|
Classification | ASTM Class 1 |
Material | Stainless Steel |
OHAUS CalPak Certified Calibration Weight Set, ASTM Class 1
ASTM Class 1 Certified Calibration Weight Set with an Accredited Certificate
Product Type | Calibration Weight |
---|---|
Tolerance | Uncertainties of less than 1/4 of the tolerance. |
Material | Stainless Steel |
Troemnerâ„¢ Individual Analytical Precision Weights, Class 4
Designed for your most demanding weighing applications
Includes | Polycarbonate case |
---|---|
Classification | ASTM Class 4 |
Packaging Quantity | 1 |
Quantity | Each |
Classification | OIML Class F1 |
---|---|
Material | Stainless Steel |
Certifications/Compliance | ISO17025:2005, ISO9001, ISO14001 environmental standard |
Density | 7.9kg/dm3 at 20°C |
Mettler Toledoâ„¢ M1 OIML Class Advanced Weight Set (M1 PL C E)
M1 OIML quality weight set housed in a plastic case includes accessories for handling and cleaning, and a calibration certificate.
Product Type | Test Weight |
---|---|
Material | Stainless Steel |
Case Material | Plastic |
Density | 7950 (± 140) kg/m3 |
Mettler Toledoâ„¢ M1 OIML Class Standard Weight (M1 PL E)
Single M1 OIML weight constructed of 304 stainless steel and housed in a plastic box.
Includes | Without certificate |
---|---|
Product Type | Test Weight |
Material | Stainless Steel |
Case Material | Plastic |
Density | 7950 (± 140) kg/m3 |
OHAUSâ„¢ ASTM Class 4 Individual Weight
Meets ASTM Class 4 adjustment tolerances and is ideal for applications requiring a degree of accuracy above general purpose weights