InterDesign Cameo Constant Tension Shower Curtain Rod &ndash; extendable 26&rdquo;-42&rdquo;, Small, White EASY TO INSTALL: No tools or hardware required  just twist, extend and lock curtain rod in place! CONSTANT TENSION: Curtain rod wont slip - patented new technology provides a secure hold. CUSTOM FIT: Tension rod adjusts and extends from 26-42 to fit your shower or bathtub perfectly. STURDY DESIGN: Curtain rod is made of rust resistant steel and plastic with a coated, non-slip foot. THE INTERDESIGN PROMISE: Bringing you elegant, affordable home products for over 40 years. The cap of the curtain rod is 4.5 Inches in diameter and the rod is 3.5 Inches in diameter