LGC Maine Standards, Cumberland Foreside, Me, has added rheumatoid factor (RF) to its Validate SP2 calibration verification and linearity test kit. Validate SP2 evaluates albumin, C-reactive protein, haptoglobin, prealbumin, and RF in a human serum base. Each kit is prepared using the Clinical and Laboratory Standards Institute recommended “equal delta” method for linearity testing and is liquid, ready to use. Users simply add the product from the dropper bottle directly into a sample cup and run in replicates. With the addition of RF, clinical laboratories can complete their required serum protein calibration verification and linearity testing, and maximize the reportable range while minimizing manual dilutions. For more information, visit LGC Maine Standards.