Rekeyable lock

A rekeyable lock, comprising:

• a lock casing formed with a lock cylinder hole, a pin replacing hole and a plurality of first pin holes;
• a lock cylinder rotatably arranged in the lock cylinder hole, wherein the lock cylinder is formed with a plurality of second pin holes, wherein the second pin holes are communicated with the first pin holes respectively when the lock cylinder is located at a first position relative to the lock casing, wherein the second pin holes are communicated with the pin replacing hole when the lock cylinder is located at a second position relative to the lock casing;
• a pin set comprising:
• a plurality of first pins respectively accommodated in the first pin holes;
• and
• a plurality of second pins respectively accommodated in the second pin holes;
• an outer casing having an inner wall defining an accommodation space for accommodating the lock casing;
• and
• a pin plug comprising:
• a main body having a first side configured to abut against the lock casing, and a second side configured to abut against the inner wall of the outer casing, wherein the second side is opposite to the first side, and a shape of the second side corresponds to the inner wall;
• and
• a protruded block protruded from the first side and configured to be inserted into the pin replacing hole for closing the pin replacing hole;
• wherein the pin plug is configured to block the plurality of second pins from passing through the pin replacing hole when the plurality of second pin holes are communicated with the pin replacing hole;
• wherein the pin plug is not rotatable relative to the lock casing when the lock cylinder is rotated relative to the lock casing.