This is the Futaba S3003 Standard Servo.
This basic servo is used in cars, boats, or where standard servos are used.
This is the replacement for the following servos, S138,S148,S22,S38 and S12.

This servo can produce high-current draw from your batteries. If using NiMH or LiPo batteries, make sure they are capable of delivering sufficient amps.

• Speed:
  
• 0.23 sec/60° @ 4.8V
• 0.19 sec/60° @ 6V
• Torque:
  
• 44 oz-in (3.2 kg-cm) @ 4.8V
• 57 oz-in (4.1 kg-cm) @ 6V
• Dimensions: 1.6" x 0.8 x 1.4" (40 x 20 x 36mm) w/o output shaft
• Weight: 1.3oz (37g)
• Connector: "J" type with approx. 5" lead

• One S3003 standard servo with preinstalled round servo horn FUTM0031
  
• Four brass eyelets
  
• Four Black rectangular rubber grommets (FUTM2348)
  
• Four servo mount screws
  
• One servo wheel 1-3/8" (35mm) in diameter
  
• One X-shape servo arm 1.5" (38mm) across
  
• One star shaped arm 1-1/4" (32mm) across
  
• Nylon gears

** you may be given a S3003 servo without box (taken out from the transmitter package) without further notice. However, it is still brand new as you can see there is no "screwed mark" around the screw holes.