With 200 colour co-ordinated tees, this product makes it extremely easy to identify the correct size tee needed for your shot: The white tees are 50mm and are perfect for drivers; they allow you to securely tee the ball up at a higher elevation without ruining your tee; enabling you to tee up higher off the ground ? hitting your ball in the same spot on the driver every time. The size of the yellow tees are 43mm and are ideal to be used with Fairway Woods in order to get a slightly more accurate hit than you would when using a driver; the size of the tee will enable you to have more control and provide less of a sidespin off the tee, creating straighter drives and leaving you in a better position to take your next shot. When using #3 - #7 irons the blue tee (37mm) in this pack will provide you with the right height to take the shot you need which will enable you to push your golf ball towards the hole. The red tee (31mm) is ideal to be used in conjunction with an open faced club, such as a sand wedge, or sand iron. The wide sole of this wedge matched with the tee size provides you with a great bounce, allowing the club head to gently glide through the sand. When you need to hit the ball higher on the clubface this needs a longer tee in order to achieve the best drive possible; with this variety pack of PGA TOUR Castle Golf Tee?s, there are 6 different colours all varying in size from 31mm to as tall as 70mm.