The Noodler's Standard Flex fountain pen (also known as the "Nib Creaper") is designed with a small, slender body, a flexible #2 steel nib, and a twist piston mechanism.  There is also a small ink window that shows how much ink is left in the pen. The body is made of a celluloid derivative which is technically biodegradable and formed from a "renewable resource" known as vegetal resin.

The Noodler's flex pens were designed to be taken apart for cleaning and adjusting. The nib and feed are easily removed and can be adjusted and heat set for optimal performance.