Philip writes – “Tslots are an aluminum extrusion building material that fits together with simple allen wrench hardware. It’s all the rage with industrial/conveyer belt building, and it’s lighter and stonger than welded metal. They’ve won some awards, and are getting a name out there. I’m using it to build a camping roof rack for my 63′ vw bus.” – Link.
TSLOTS – Extruded aluminum structural building material