- Ingersoll Rand IQv Series Cordless Straight Die Grinder - 14.4 Volt, Model# GS25 .35 HP motor delivers power that exceeds most air die grinders Advanced gearing with same head and collet as Ingersoll Rand air die grinders Variable-speed motor control with safety lock 27,500 RPM free speed Compatible with all 14.4V IQv batteries, including Ni-Cd and Lithium Ion