SpeedPuck Speed Accuracy: 0.2 Knots, Heading Resolution: 1, Display Update Rate: 2Hz Water Resistance: 3m / 10 ft (IPX8) Dimensions: 115mm / 4.5" diameter, 27mm / 1.06" thick, weight (including batteries): 295g / 0.65lb Box Contents: USB Cable, Velocitek Sticker, Quick Start Guide, Lanyard, Mounting Cradle No batteries included.