Automatic Twistlock

A twistlock comprising a housing, and a shaft journalled into the housing said shaft having a first end protruding from a top of the housing with a cone formed thereon said cone being elongate radially, relative to the shaft, for passing through a first elongate slot of an upper container corner casting,

• an upper surface of said cone being beveled so that sides of the first elongate slot can force the cone and shaft to rotate from a locked position to an unlocked position to enable passage through the first elongate slot, and a lower surface of said cone being beveled so that the sides of the first elongate slot can force the cone and shaft to rotate from the locked position to the unlocked position,
• means for biasing the shaft, wherein the shaft is biased to the locked position,
• the housing comprising a central flat portion to be positioned between the upper container casting and a lower container casting,
• a lower protrusion extending from a bottom of the central portion of the housing the protrusion comprising a first part closest to the central portion and being dimensioned to pass through a second elongate slot in the lower container casting and allowing at least some rotation within the second elongate slot axially with respect to the shaft, and a second part of the protrusion further from the central portion including two tongues diagonally opposed, extremities of which tongues are positioned such that the protrusion can fit through said second slot in a first rotational position, the protrusion being so configured, that once the second part has passed through the elongate slot, the housing can be rotated to a second rotational position where a respective upper surface of the two tongues bear against diagonally opposed surfaces of the inside of the casting adjacent said slot.