This is a lightweight modular conversion ring for a Discus circle to Shot Put, Hammer, Weight Throw Circle.   NOT INTENDED AS A STANDALONE CIRCLE
 
Using keyed foam mats we cut out the proper size insert to take the 2.5-meter circle to a 2.135-meter throwing circle. We use a large laser router to cut a smooth accurate insert to the proper size. The pads lock together to form the insert.  The insert fits snugly in the discus circle.  The mats are heavy-duty 3/4  inch thick. The circle is accurate to within .5 diameter due to the expansion and contraction of foam.  We get material in 3 different colors and depending on availability the one shipped maybe sky blue, silver/grey or black.
 
0, 90, 180 270, are marked on four segments to give visual to the proper foot placement for turns.  Depending on availability they will be on contrasting segment colors or labeled in contrasting ink.