Futaba GY401Heading Hold Gyro 

Delivers high performance for 30- to 60-size helicopters 

Has remote gain feature and transmitter-controlled switching to AVCS 

Operation is almost 4 times faster (270Hz) than conventional gyros

 Measures 1" x 1" x .8" (27x27x20mm), and weighs 0.6 oz (27g) 

  One GY401

One plastic adjustment screwdriver

Three mounting pads