Roy Conklin invented and patented the self-filling pen known as the Crescent Filler™, and now it is recognized as the world's first practical self-filling fountain pen.
 
In 1903, Mark Twain expressed the virtues of this unique self-filling fountain pen by saying, “I prefer it to ten other fountain pens, because it carries its filler in its own stomach and I can not mislay even by art or intention.” Becoming the official spokesman for The Conklin® Pen Company, Mark Twain discovered yet another benefit to Conklin’s Crescent Filler™ stating, “Also, I prefer it because it is a profanity saver; it cannot roll off the desk.”  
 
Bottle fill only.
Steel nib.