Metal extension planks

Claim 1

An extension plank comprising first and second elongated sections that telescope from a plank maximum length to a plank minimum length, each said elongated section comprising: an outboard portion, an inboard portion and a plurality of parallel tubular elements that extend therebetween, said tubular elements all being of rectangular cross-section defined by a pair of short sides and a pair of long sides, said outboard portion comprising an elongated U-shaped channel defined by a base section and a pair of side sections, the outboard ends of said tubular elements being fixed into said U-shaped channel spaced apart from each other a distance greater than the width of said short sides and with said long sides spanning the space between said channel side sections, said inboard portion comprising first and second straps having in-turned ends and a plurality of guide saddles, said guide saddles being U-shaped defined by a base web and a pair of short side webs, said side webs being spaced apart a distance substantially equal to the width of said short sides, said first strap being fastened to each of said tubular elements with one of said guide saddles sandwiched between a short side thereof and said first strap so said side webs project away from said first strap, and said second strap being fastened in the manner of said first strap to the other short side of said tubular elements, said inboard portion of said first elongated section slideably enclosing said tubular elements of said second elongated section and said inboard portion of said second elongated section slideably enclosing said tubular elements of said first elongated section whereby said elongated sections can telescope with each other and said guide saddles provide free, easy sliding action between said elongated sections.