In this paper a brief overview of the role and the possibilities of pneumatic systems in the miniaturization trend is given. In the beginning, the history of pneumatics as a science and technical discipline is explained, alongside its good properties and shortcomings, typical elements of a pneumatic system and its actuators, after which pneumatic cylinders are described in detail. As an introduction to the subject of the paper, a brief explanation of the miniaturization trend is given, followed by its effect on pneumatics. Special attention is given to the miniature pneumatic cylinders, both in milimiter scales and in micro scales in which innovative methods of sealing are used, each of which is then additionally explained. Clearance seals are chosen for analysis in this paper. Aftew reviewing the existing cylinders, geometry parameters are decided on and the design of the cylinder is done. In order to be able to test its characteristics in real situations, it is produced and then tested in the laboratory. Tests are done by means of a camera and by using a data acquisition system and the results are compared with the theoretical calculations. Further analysis of the results is given last alongside a commentary of the real characteristics of the cylinder.