HFRR standard specimens are sold as a pack of 100 upper and 100 lower specimens. The upper specimen is a 6mm diameter ball that is loaded into the upper specimen holder, and the lower specimen is a 10mm disc that is loaded into the lower specimen holder.
The specimens are manufactured to comply with ISO 12156-1, ASTM D6079, ASTM D7688 and IP450 diesel fuel standard test methods.
Letter