DRAGON ELECTRONICS CO DHT-300 / DHT-310Plus Hardness Tester 

Features:

• Pocket Size, Easy To Operate
  
• High Contrast OLED Display 
  
• High Accuracy +/- 4HL (0.5% At 800HL)
  
• Conveniently Exchange Between Impact Device D And DL
  
• Automatic Orientation Correction
  
• Work With Mini-Printer Thru Bluetooth (DHT-310 Series)
  
• For Most Metals
  
• Based On The Hardness HL Value, Conversion Can Be Performed ToHRB, HRC, HV, HB And HS
  
• USB Interface For Both Recharging And Data Transfer To PC With Software Free
  
• Internal Memory In A Batch Of 1250 Average Readings
  
• Lower And Upper Limits Setting With Low-High Display Judge
  
• Works On 3.7V Rechargeable Lithium-Battery With Working More Than 16 Hourscontinuously
  
• Auto Shutdown After 5 Minutes
  
• Conforming To ASTM A 956
  
• Multi-Languages
  
• Multi-Hardness Standards