Product Material: Nylon Size: 17*11.5CM Color: black Quantity: 1 pcs Package content: 1 pcs * Training alerter 1. Application: Through the sound of our golf training aid, golfers can detect their left arm curvature error in order to keep the left arm in a straight position; Therefore, an effective and desired blow can gradually be formed; Suitable for all golfers or golf lessons, especially beginners. 2. Sound Prompt Incorrect Posture: The golf swing trainer is an integrated alarm device made of special material that immediately generates a sound when you bend your elbow while swinging. It alerts you that you are not in the correct posture; You should adjust the posture and keep your left arm straight. 3. Adjustable and easy to carry: Strong Velcro and buckle make the golf training aids swing adjustable, easier to put on and take off; The thick plastic buckle does not scratch the skin like other thin metal buckles; It suits most people's arm. 4. Not easy to change and better to warn: Compared to other suppliers which is a simple belt, our golf swing trainer is around the entire elbow, ours is not easy to move and it can better warn golfers 5. Breathable material: Our golf swing training aid is made of high quality, breathable nylon cloth + webbing + Velcro fastener, is durable and light; It won't pressure you.