Seiko NH15A

The NH15A is an automatic movement manufactured by Seiko in Japan. Introduced in 2009, it is based on the NH05 caliber with a larger mainplate and rotor, measuring 23.8mm in diameter. The movement features hand winding, hacking seconds, and a date complication. It uses Seiko's Diashock shock protection and Magic Lever winding system. The caliber was discontinued after the NH15B was released.