Duckworth Prestex Watch Lostock Blue 40mm Quartz Chronograph Bracelet D547-03 ST. A 40mm diameter round case, quartz chronograph. It is the very first round watch and very first 40mm case size. It is named the LOSTOCK after the residential suburb of Bolton of the same name. Lostock which is the home of Bolton Golf Club and Bolton Ternnis Club. And where Neil Duckworth and generations of Duckworths have played these fabulous sports. A fitting name for a robust and stylish sports chronograph.