These are for when you have the gimbal off of the Blade Chroma Camera Drone. They can be used while doing flips, or you can set them on cinderblocks for takeoff and they stay out of the view of the camera. The "U" shaped things on the bottoms are for 1/2" dowel rods. If I had the skids 3D printed it would be an extra $60 (Which I have for sale here https://www.shapeways.com/product/KCMTRMX28/blade-chroma-small-landing-gear?optionId=60206744&li=more-from-shop). This way you can adjust how much skid you want in the front and back. Dowel rods are $2 at Lowes or any hardware store and that is way better than $60. Simply glue the 1/2" dowels to the bottom using your favorite super glue. The picture shows them interlocked which is how they will print to save machine space.