Try this oval-shaped curtain rod when you want to mount curtains inside of the window frame. The spring allows you to adjust the length of the rod without having to add any holes to your walls. For mounting window treatments inside a window frame No mounting hardware required 5/8" wide Steel/plastic.  Included: 1 Set of Mounting Hardware Features: Adjustable Use: Indoor Rod Diameter: 5/8" Base Material: 2% Plastic, 98% Steel Curtain Rod Length: Under 28in Care: Wipe Clean Curtain Rod Type: Tension Curtain Rods Country of Origin: Imported