Rotatable lighting apparatus

A rotatable lighting apparatus, comprising:

• a terminal;
• a base, wherein the terminal is fixed on the base, an end of the base opposite to the terminal forms a junction portion, and the junction portion includes at least one protruding part;
• a rotatable lamp holder, pivoted at the junction portion of the base and comprising:
• a heat dissipation part, comprising a plurality of restricting trenches for fastening to the protruding part;
• and
• a lighting source, fixed on a single face of the heat dissipation part;
• a passing-through device, passing through the base and the rotatable lamp holder, and the rotatable lamp holder is able to move relatively to the passing-through device along a moving-axis;
• and
• a bellow device, connected to the base and the rotatable lamp holder, when a tensile force is applied to the rotatable lamp holder, the rotatable lamp holder is capable of moving relative to the base along the moving-axis, so that the protruding device is departed from the corresponding restricting trench, and thus the rotatable lamp holder is capable of rotating relative to the base, when the tensile force is removed, the rotatable lamp holder is fastened to one of the restricting trenches by resilience of the bellow device, so that the rotatable lamp holder is fixed on the base.