Tachometer Features - High Starting Torque - Sealed Ball Bearings - Replaceable Brushes - Dynamically Balanced Armatures - Shaft Diameter up to 5/16" - 2 Year Warranty - Custom Designs Available The DC PM Tachometer Generators provides a simple and dependable means to obtain your speed measurements. They are designed to meet the need for high output DC models in commercial and industrial applications. They feature rugged design and performance throughout the 5 to 60 volts per thousand RPM range. With long life and trouble free service, these tachometers will help you measure and control your product quality and performance at a low cost.