Radius 145 mm / 5-3/4 inches. 45°. Charlie's Tips: These pieces are 45 degrees each. That means that 4 pieces make a half circle. The radius is 145mm, which is close to 5-3/4 inches. That means that a half or full circle has a diameter of 11-1/2 inches. This is measured from the center of the track piece to the center of the track piece. The second picture shows the track geometry. For a full circle you need 8 pieces For a half circle you need 4 pieces For a 90 degree turn (quarter circle) you need 2 pieces For a wider circle, use 8520 or 8521 For an even wider circle, use 8530 or 8531 If you would like a full box, order 10 pieces, they are packed in box of 10. This is the tightest Z-scale curve available. It gives you a tighter curve than is possible with flex-track Read more about the Marklin Z Scale Extension SET system. Read more about the Marklin Track Geometry.
