I had received as a gift some time ago a fountain pen with pump, I found it very convenient charging principle. Therefore, I was looking for my other ink pens a standard pump, I love to use different colors of ink. I found it on Amazon (impossible to find in stores around my home) and I am very happy. I tried it with red opera, perfect result. It is true that there is no manual, but the filling is very simple: we dip the tip of the pump into the ink bottle is turned and the tip is filled, and wiped put in the pen like a standard ink cartridge.