7 construction machines and equipment; namely, pile drivers, pile hammers, pile extractors, pile hammer leads, pile hammer supports, hydraulic breakers, demolition hammers, casing drivers, earth augers, drilling machines, drill heads, tunneling machines and instruments for controlling the operation thereof sold as a unit, boring machines, boring heads, trench shoring equipment, directional drilling machines, hydraulic power units used as a source of hydraulic power with any of the aforementioned machines