The utility model discloses a spanner which comprises a handheld rod and clamping opening end heads. The spanner is characterized in that at least one end of the handheld rod is provided with two clamping opening end heads. At the end of the handheld rod, the two clamping opening end heads are symmetrically connected on two sides of the axis of the handheld rod, and each of two ends of the handheld rod is connected with two clamping opening end heads. Each clamping opening end head is a circular ring, and teeth are evenly distributed on the inner hole face of the circular ring; or each clamping end head is a circular ring, and an inner hole of the circular ring is in a hexagon shape; or each end clamping end head is a round disc, and a rectangular notch is formed in the round disc. By means of the spanner, the number of spanners which are carried to a work site is reduced, maintenance operation is enabled to be convenient and rapid, the frequency for replacing the spanners during the operation is lowered, work efficiency is improved, and safety production is guaranteed.