Multistage selective cart clamp

A system of joined adjacent tubular structures comprising:

• adjacent tubular structures including adjacent structural tubes;
• and
• an apparatus including:
• a tube retention body including a pair of substantially parallel retention bolts configured to be inserted in substantially parallel aligned relation within end portions of the adjacent structural tubes and retain the adjacent structural tubes;
• and
• an alignment lock plate pivotally affixed to the tube retention body configured to retain and lock together a pair of the adjacent structural tubes in aligned substantially parallel relation via a toolless connector.

A method of joining two adjacent tubular structures, the method comprising:

• inserting an apparatus into adjacent structural tubes of the adjacent tubular structures including the adjacent structural tubes, wherein the apparatus includes:
• a tube retention body including a pair of substantially parallel retention bolts configured to be inserted in substantially parallel aligned relation within end portions of the adjacent structural tubes and retain the adjacent structural tubes;
• and
• an alignment lock plate pivotally affixed to the tube retention body configured to retain and lock together a pair of the adjacent structural tubes in aligned substantially parallel relation via a toolless connector;
• and
• pressing an inner face of the alignment lock plate flush with the adjacent structural tubes.