The Tissot 28.21 watch movement features a pin-lever escapement and a stem mechanism without a setting-lever spring. Late samples of this movement have a glued hairspring terminal. The train and hand gear of the movement are strangely driven separately by the barrel. This movement incorporates several functions, including automatic winding, sweep second hand, day display that can be set by +/-24h, and a date display that can be quickly set by reverse setting. The Tissot 28.21 movement is a pin lever movement that was used approximately in 1975.