7 [Belt conveyors; conveyor belts; mud collectors; bulldozers; ploughs; coulters, ploughshares; cutting wheels; compressors; road making machines; cutting machines; machine parts, namely, cutters; hoppers for mechanical unloading; dust removal installations for cleaning; mechanical winders for flexible pipes; machine parts, namely, drivers; excavators; mine extractors; drilling machines; tar spreaders; coal cutters hydraulic controls for machines and motors; hydraulic motors; hydraulic turbines; machine parts, namely, blade holders; machine parts, namely, saw blades; machine wheels; mixing machines; handling apparatus for loading and unloading; grinding machines; machine parts, namely, sharpening grinders; pneumatic controls for machines and motors; pumps; machine parts, namely, tool holders; machine parts, namely, pressure reducers; machine parts, namely, pressure regulators; machine parts, namely, pressure valves; blowing machines; earth moving machines; vibrators all for industrial use and all for digging trenches, depositing tubes, cables, tubular sheaths or the like in trenches, and for back filling trenches]