This is the Futaba S3151 Digital Servo. Great for a wide variety of R/C models. FEATURES: Digital technology gives performance advantage One Ball Bearing and one Metal Bushing Nylon gears One year warranty INCLUDES: One S3151 Digital servo with preinstalled servo horn Four Rectangular Grommets Four Mounting Screws One Large Round Horn One Six Arm Horn One Four Arm Horn SPECS: Speed: 0.21 sec/60° @ 4.8V Torque: 43 oz-in @ 4.8V Dimensions: 1.6 x 0.8 x 1.4 in (41 x 20 x 36mm) Weight: 1.5oz (42g)