The first NA Miata rolled off the production line over 30 years ago, and the last NB rolled out over 15 years ago. Most of these cars have put on many miles over the years. A lot of them have gone through multiple timing belt and water pump services over the years (hopefully). There are some low mile cars out there that never had this service done!
The Maruha timing belt is reinforced and made with better quality materials. Their testing from the manufacturer shows the longevity of these belts are far superior to the OEM equivalent. If a timing belt service is due, add this reinforced Maruha Timing Belt to your parts for peace of mind knowing it will have less probability of failing due to age/miles.