Run around corners, edges, and large obstacles! With the "Flex Corner" extension, every KOSMOS Gecko Run marble run becomes infinitely flexible. Whether there's a window frame in the way, a gap between the fridge and shelf needs to be bridged, or you want to build around a cabinet – all of this is now possible! Simply place one of the two Flex Corners between two track elements, and the marble will roll around the curve. Additional track elements expand the range of the run and open up entirely new possibilities. Ever built in a cross pattern? Just give it a try and build anywhere that is smooth and vertical!.