US-BASED Stone Construction Equipment manufactures a range of power trowels which are available in diameters of 61cm, 91cm and 122cm. According to Stone, its smooth operator trowels are dynamically balanced with an extra strong cast iron spider, a rotating stabilisation ring and infinitely variable blade adjustments.

The smooth operator trowels are also equipped with a shock-mounted ring guard to reduce vibration, and a patented Dyna-Clutch system which can stop blade rotation without shutting off the engine. The trowels are also available with a choice of engines – Honda, Briggs, Robin and Wisconsin in 4-blade models – and can be outfitted with either finish or combination blades.