Shipping Policy : 1.Battery and Liquid not included during the shipping. 2.WE ship the products by DHL ,FEDEX ,UPS or other express etc. Applications: *Used to measure rotative velocity, surface speed, frequency of motor. Applicable to the product departments of motor, fan, paper-product, chemical fiber, washing-machine, automobile, airplane, steamer etc. * DT-2858 combine PHOTO TACH. & CONTACT TACH.. Also can test surface speed. . Parameters: *DT-2858 Measurement Range: Laser : 2.5 ~ 99,999 r / min ; Contact: 0.5 ~ 19,999 r / min ; Surface Speed: 0.05 ~ 1999.9 m / min , 0.2 ~ 6560 ft / min . *Resolution: Tachometer: 0.1 r/min(0.5~999.9 r/min) ,1 r/min(Over 1000 r/min) ; Surface Speed : 0.01 m/min(0.05~99.9 m/min) , 1 m/min(Over 100 m/min) ; 0.1 ft/min(0.1~999.9 ft/min), 1 ft/min(Over 1000 ft/min) . *Accuracy: +-(0.05% n + 1 d) . *Sampling Time: 1.0 s (Over 60 r / min). *Test Range Select: Automation . *Memory: Max / Min / Last Value . *Time Base: Quartz Crystal . *Laser Tach Detecting Distance: 50~150mm/2~6inch(Typical),Max,300mm/12inch . *Power Consumption: 80 mA (Testing). *Operating Temperature:0 ~ 50 Degree . *Power Supply: 4 x 1.5 V AA size (UM-3) battery .(Battery not included in the package） *Dimensions: 215x74x32mm . *Weight: About 280 g . Package includes: Standard Accessories: 1* Main Unit 1* Carrying Case 1* Operation Manual 1* Reflective tape 350mm 1* Surface Speed Test Wheel(AS35C) 1* Cone Adapter(AS35A) 1* Funnel Adapter(AS35B)