The High Pat on Horse ( 高探马 Gāo tàn mǎ) is a common posture found in t'ai chi ch'uan. Typically at the end of the posture the left hand is in a palm looking up at Dan tian height, while right hand is held at shoulder height, with the arma almost fully extended. The left leg is extended, while the the rigth one is backward in a high Qi Xing Bu posture and the weigth is mostly supported on this one.
The High Pat on Horse is an easy posture to learn from beginners. Just imagine you are holding a rein in yourleft hand, and clapping the muzzle with the right.
This posture uses a sort of Lieh (Spliting) force and the Chung Ting (Central stance) movements.