Abstract: A pneumatic or gas spring includes a cylinder filled with gas under pressure and a piston which is slidably movable in the cylinder, the piston being fitted at the end of a rod which is gastightly and slidably guided through a closure bottom of the cylinder. The piston rod is lockable in its extreme extension position out of the cylinder by means of a snap ring fitted on the piston rod which cooperates with a localized constriction or step protruding inwardly from the cylinder wall adjacent its rod guide bottom, the snap ring having an external diameter intermediate between the inner diameters of the cylinder and the constriction or step.

Abstract: The cylinder of a gas spring has a bottom constituted by a plug designed for allowing gastight penetration of a plunger rod into the cylinder thanks to a seal having a lip surrounding this rod in sliding frictional engagement therewith. The seal is sandwiched between two annular holders respectively located on the outer side and on the inner side of the seal. The outer holder plays the part of a mechanical guide for the plunger rod whereas the inner holder plays the part of an oil retainer for lubrication of the seal lip.

Abstract: A tube of a shock-absorber is mounted inside an iron ferrule formed with apertures in which are inserted projections as previously formed on the tube. The ferrule is formed integrally with tabs or legs for securing to a vehicle part such as a wheel axle.