The "Class" determines the weight's tolerance (how close it is to the exact mass). Typical Class ASTM 1 / OIML E2 High-precision balances (0.0001g) General Lab/Quality Control ASTM 4 / OIML F1 Precision balances (0.01g to 0.001g) Retail / Shipping ASTM 6 / OIML M1 Floor scales, postal scales, food prep Personal / Hobbyist Jewelry scales, coffee scales, home use Visual Selection Guide
: Reliable mid-range and professional options available through scientific suppliers like Fisher Scientific. where to buy calibration weights
: Highly regarded for high-precision analytical weights. Users on metrology forums note their premium pricing but exceptional quality. The "Class" determines the weight's tolerance (how close
Buying calibration weights depends on your scale’s precision. High-end labs require ASTM Class 1 weights (Rice Lake/Troemner), while home jewelry or coffee scales are best served by affordable M1 or M2 stainless steel sets . Where to Buy: Top Vendors Users on metrology forums note their premium pricing
: The gold standard for industrial and laboratory weights. They offer ASTM Class 1 to 6 weights with optional NVLAP accreditation.