Fowler Pistol Grip Bore Gage Set with Bluetooth Output Specifications include... 0.750" - 4.00" / 20-100mm Bore Gage Set 0.00005" / 0.001mm Resolution 6 Heads, 1 Handle, 4 Rings Fowler/Bowers XT Holematic Pistol Grip range of bore gages offer extended travel with fixed anvils. The pistol grip handle incorporates a constant measuring pressure to eliminate operator "feel". Special Features: Simple, two button operation Large easy-to-read swivel display Self-centering heads RS-232C output Two preset memories Non-removeable anvils All gages and heads are serialized Tungsten carbide measuring faces on all 3-point heads from .5" (12.5mm) and up. Setting rings included in all sets Includes UKAS certificates for all pistol grips and rings. Send data directly to a Bluetooth cell phone or Tablet with the FREE Sylvac BT Smart app. To be able to send data to a PC, you will need to also buy the Fowler USB Bluetooth Receiver for that PC. You can have up to 8 different gages sending data to the 1 PC through this Bluetooth Receiver.