GRL4000-80CH Bosch 18V Revolve4000 Connected Self-Leveling Horizontal Rotary Laser with uCAL GRL4000-80CH Bosch 18V Revolve4000 Connected Self-Leveling Horizontal Rotary Laser with uCAL delivers a comprehensive solutions for precise outdoor/indoor leveling and features Dual Dial-In Slope that allows slope angle adjustment on both the X- and Y-axes for grading applications. GRL4000-80CH Bosch 18V Revolve4000 Connected Self-Leveling Horizontal Rotary Laser with uCAL is powered by a Bosch CORE18V 4.0 Ah battery for extended runtime, features an alkaline adapter to use four (D) cells and is engineered with a cage overmold, innovative handle design and is built to IP68 dust- and water- protection standards and a Bluetooth® connective to a connected device linking to the Bosch Leveling Remote App. GRL4000-80CH Bosch 18V Revolve4000 Connected Self-Leveling Horizontal Rotary Laser with uCAL features uCAL for user calibration and avoids tool down time and provides confidence that the laser is accurate.