Master cylinder with protective end

The cylinder (1) has an end (3) arranged opposite to an element e.g. battery, of an engine and another end (4) integrated with a brake system. An insert (7) is assembled on the former end of the cylinder, where the insert comprises a contact surface (10) e.g. round surface, at an end (9) of the insert opposite the cylinder. The contact surface is arranged opposite the element and not perpendicular to a development axis (6) of the cylinder. The contact surface of the insert is developed in a plane inclined with respect to the development axis.