Here are some key features and characteristics of the EMAX ES3004/ES3104 servo:

Metal Gear Train: The servo features a metal gear train, enhancing its durability and making it capable of handling higher loads and stress compared to servos with plastic gears. Metal gears are essential for applications where strength and longevity are important.

Analog Servo: The ES3004/ES3104 is an analog servo, meaning it operates using traditional analog control signals, typically in the form of PWM (Pulse-Width Modulation) signals, to adjust its position. Analog servos are commonly used in various RC applications, especially when precise positioning is not the primary concern.

Specifications: The servo's specifications include a torque rating of 3.5 kg/cm (kilogram per centimeter), a speed of 0.13 seconds per 60 degrees rotation, and a 23-tooth spline configuration (23T). These specifications provide information about the servo's torque output, speed, and spline type, which is essential for selecting the right servo for your specific application.

17-Gram Weight: The 17-gram weight classifies this servo as mini-sized. It's relatively compact and lightweight, making it suitable for a variety of RC airplane models.

Application: The EMAX ES3004/ES3104 servo is designed for use in RC airplanes, particularly for controlling various components like control surfaces (ailerons, elevators, rudder), landing gear, or other mechanisms.

Voltage and Current Requirements: Check the voltage and current requirements of the servo to ensure compatibility with your power source, such as a receiver or servo controller.