Pretensionable locking system

A pretensionable locking system for use in a medical-technical instrument, wherein the locking system comprises:

• an outer locking body with an inner thread;
• and
• an inner locking body with an outer thread;
• wherein in a pretensioned position, the inner thread lies against the outer thread in a first longitudinal axial direction and is pretensioned against the outer thread,
• wherein in a locked position, the outer locking body is fixed on the inner locking body by screwing the inner thread onto the outer thread,
• wherein the outer locking body has a resilient retaining element that projects radially inward,
• wherein the inner locking body has a rigid bulge that projects radially outward,
• wherein in the pretensioned position, the retaining element lies against the bulge in a second longitudinal axial direction that is opposite the first longitudinal axial direction, and
• wherein the bulge is in the form of a double ramp with a rising ramp surface and a falling ramp surface adjacent thereto.