This is the GY401 Gyro with SMM Technology from Futaba. This is a High Performance, Compact and Lightweight (AVCS) Angular Vector Control System gyro developed for model helicopters. Because the sensor and control circuit are integrated, it is simple to install. FEATURES: AVCS System: Since the rudder trim changes (caused by wind and other meteorological changes); the front, rear, and other heli attitudes change and are automatically cancelled; tail (rudder) operation is easy, making it perfect for 3D flight. (also known as Heading Hold Gyro) SMM Gyro Sensor: Use of this newly developed technology virtually eliminates rudder trim changes during flight (see COMMENTS). Digital Servo Compatible (DS Mode): DS mode makes it compatible with Futaba digital servos. This maximizes the high-speed response performance of the Digital Servo. Remote Gain Function and Mode Switching Function Remote: Gain function allows sensitivity switching from the transmitter and mode switching function allows AVCS/normal gyro mode switching. Integrated, compact and lightweight design made possible by high density mounting technology. Conductive Resin Case: This case improves EMC (Electrostatic and electromagnetic interference) resistance. INCLUDES: One GY401 gyro One mini plastic adjustment screwdriver Three mounting pads One instruction sheet SPECS: GY401 Gyro- Length: 27mm Width: 27mm Height: 20mm Weight: 27g Voltage- use only with a 4.8V battery. (if you use it with a higher voltage battery it needs to be regulated to 6V) COMMENTS: Can be used in helicopters and airplanes (Due to 0-100% Gain Adjust). The new SMM (Silicon Micro Machine) technology is the integration of mechanical elements, sensors, actuators and electronics all brought together on a common substrate chip. This hobby industry first, results in a gyro sensor with an unprecedented level of functionality, reliability, and sophistication. This will not work with the JR Digital Servos. These have a different pulse. KLH11/20/00 ir/jl updated jpg 3/16/06