Thank you very much for your order. The Laser Rangefinder warranty period is one year, please send me a meage if you have any questions. I will provide after-sales service to you. Please contact us for any question before you leave a negtive feeback, we will solve all problems, which will definately satisfy you, thanks. The multi-function version M/Yard switching method is to pre and hold the two buttons for 3-5 seconds Laser rangefinder for Hunting Multinfunctional application: 1.Laser rangefinder for Golf: Golf 600M Yard:Unit: M/Yard Straight line distance mode Golf mode Flagpole lock and vibration (thevibrationmethod is to vibrate after the flagpole is locked) Slope Compensation Angle switch: Manually open and close the angle. Hunting 1000M: Suitable for hunting outdoor sports camping. Camouflage appearance, high cost performance hunting rangefinder. Power Supply:USB Rechargeable, built-in lithium battery USB charging Product Size:96x34x67MM/3.78x1.34x2.64in Measuring distance mode All-in-one machine mode (angle/height/horizontal distance) Scan mode Two-point height measurement mode Speed measurement mode Golf Slope Compensation Modewith slope compensation ,novibration Data storage function Multifunction 600M: Power Supply:USB Rechargeable, built-in lithium battery USB chargingProductSize:96x34x67MM/3.78x1.34x2.64in Straight line distance mode All-in-one machine mode (angle/height/horizontal distance) Scan mode Two-point height measurement mode Speed measurement mode Golf mode Flagpole lock and vibration (the vibration method is to vibrate after the flagpole is locked) Slope Compensation Angle switch: Manually open and close the angle. Data storage function Unit: M/Yard