Stone Smooth Operator power trowels are available in 24-, 36-, 46-, and 48-in. diameters and balanced with a cast-iron spider, rotating stabilizing ring, and variable blade adjustments. All machines are available with a choice of engine: Honda, Briggs, Robin, or Wisconsin. The Dyna-Clutch system stops the blade from rotating without turning off the trowel. A shock-mounted ring reduces vibration and chatter for increased operator comfort. Finish or combination blades are available. Stone Construction Equipment Inc. 800-888-9926.