Pickup-truck tailboard lock

A tailboard lock for locking a detachable tailboard on a pickup truck, said lock comprising:

• a lock main body formed with an accommodating groove in the interior, said lock main body having one side axially bored with two through insert holes at two sides of said accommodating groove, a lateral hole formed to cross said two insert holes at their rear portion;
• a lock core received in said accommodating groove of said lock main body to be rotatably positioned therein, said lock core having its first end bored with a key hole and its second end disposed with two interacting engage members, said engage members extended in said lateral hole of said lock main body, said accommodating groove having its opening fitted with a fixing ring;
• a positioning casing covered around said lock main body, said positioning casing having its opening fitted with a cover, said cover bored with a key insert slot at a location matching with said key hole of said lock core, said key insert slot provided with a slide lid able to be slidably opened and closed;
• a shackle formed with two parallel rods, said two rods having their outer ends connected by a curved member, said two rods having their inner surface cut with a plurality of one-way lengthwise fitting notches;
• and
• a protective cover covered around said positioning casing and said cover.