This is a unique way to provide your birds with healthy, full-spectrum light. This patented light design will fit cages with flat tops and arch tops. No hardware needed, simply place eyelets between the cage bars for a secure fit. Eyelets can be used for hanging toys also! The shade is attached to the grill with 3 wingnuts which allows you to change the bulb easily. The bulb is housed within the shade and will sit 4″ from the top of the cage.