Durston Tools’ PrecisionFit™ Marked Aluminium Ring Mandrel & 31 Ring Set, providing USA ring sizing from 1-16. Our PrecisionFit™ technology is the most accurate ring sizing system in the World, guaranteed to provide a perfect sizing between mandrels and rings. PrecisionFit™ is the USA’s favourite ring mandrel range, with over 20,000 sold in the USA per year!
