I have a 25 year-old Concord mariner – an ultra-thin quartz watch that I love. The stem came lose and the watch was sent back to the manufacturer who could not repair it as they no longer make parts for this watch. Fortunately I discovered Manhattan Time Service. They had the needed parts, gave me a very quick and fair estimate of the costs and performed the repairs expertly and quickly. The staff is polite, helpful, and totally professional. I would highly recommend them.