This product promotes better shoulder girth by avoiding excessive flexion of the arm joints. Helping golf beginners and some amateurs learn how to swing better. Greater flight distance, accuracy and scoring, arc and fully extended arms to maximize clubhead acceleration. Tie the product to your arm for longer, more control golf rights. Instructions for Use: The product is installed on the 90-degree flexible part of the right arm, just near the nylon buckle and wear firmly. Function: Help correct the swing posture, this product can correctly extend the arm during the backswing, release the arm and hand during the downswing correctly, and promptly correct common golf swing defects. Colour: Black Material: Plastic Package Contents: 1 * Golf swing trainer Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.