Stopper for leaky Markus office chair gas cylinder

Too lazy or cheap to buy a replacement gas cilinder for you Ikea Markus? Print this stopper to prevent the dreaded sag. Easy to print and in one piece for you to not waste your time. 

I printed in PETG to prevent warping with extensive use. With a  0.3 layer and 3 wall thickness it holds up well but you could always add more material for more strength.