Qlipp Plus Tennis Sensor
Tech specs 
Dimensions29.55mm length x 25.66mm width
Weight8 grams
Battery life6 hours
Water resistanceNo
Internal memoryNo
Displayvia smartphone or smartwatch.
SensorsAccelerometer and gyroscope.
Smart watch compatibleYes
RemovableYes
Compatible brandsAll. Doubles as a dampener.
Metrics 
PowerYes
SpinYes
Impact locationYes
Number of shotsYes
Shot typeForehand, backhand, serve, overhead
Spin typeTop spin, slice, flat
Swing speedYes
Ball speedYes
Live trackingYes
Video functionYes
OtherThis version of the sensor includes an L-shaped USB cable so you can charge without taking the sensor off your racket, and a carrying case.
Links 
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