These googles are based off a design that was made for 52MM Camera filters. These goggles are slightly smaller than DAstronomer's. I made two masks and was able to purchase some cheap sunglasses and shape the plastic lenses to fit inside the lens holder. The visors on the front cover are intended to be glued on to the front ring. This way you can glue them on straight, to fit the way the goggles sit on your face/mask.Printed in ABS on a MonoPrice Dual extrusion printer, Sanded and finished with an Acetone Vapor bath.