The 21-inch long yellow Putting Arc T3 has been a very popular putting aid for the top touring pros, the top amateurs, and the best college players over the years. It is small, light (9 oz), portable, and easily fits into a golf bag. The T3 Putting Arc was specifically designed for outdoor use and should be anchored to the green with tees. The Putting Arc T3 is very durable and resistant to heat, UV radiation, and impact shock. Many TOUR players we know have had the Putting Arc T3 in their bags for years. Designed for 5 to 10-foot putts, the T3 features the same natural arc as the larger models but is everything you need to learn the stroke and ensure you get the ball starting down your aim line very precisely. Tee holes are included to secure the T3 to the green while you practice. We recommend buying the Putting Arc MS3 or MS-3D for indoor or outdoor use and using the T3 as a portable model. However, non-skid tape or hook fastener can be applied to the underside to use the T3 indoors. In a practice session, you can putt hundreds of balls from the exact same spot with the exact same setup until you feel like there is nothing you can do other than start the ball rolling toward your target. It’s a huge confidence builder!