JR 3121

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*Based on known specs.

Technical Specifications

Last Updated: 2026-10-22

Identity
Brand
Product Number	JRPS3121
Category	Hobby
Discontinued	Yes
Performance
Torque	6.0V 56.00 oz-in 4.8V 46.00 oz-in Above Average
Speed	6.0V 0.20 sec/60° 4.8V 0.22 sec/60° Below Average
Physical
Weight	0.84 ozAverage
Dimensions	L 1.30 in W 0.58 in H 1.02 in
Drivetrain
Motor Type	Coreless
Gears	Plastic
Rotation/Support	Dual Bearings
Control & Signal
Modulation	Analog
Electrical & Environment
Operating Voltage	4.8–6 V
Connectivity
Connector	JR (Universal)

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Disclaimer: Most data is sourced from the manufacturer. Some data is sourced from our loyal community and with the help of AI. We aim for accuracy but are not responsible for inaccurate information.

Compatible Hardware

Amazon eBay

*Based on known specs.

Class Comparison

Torque	Above Average Stronger than 78% of 77 Analog Mini servos at 4.8V
Speed	Below Average Faster than 11% of 77 Analog Mini servos at 4.8V
Weight	Average Lighter than 35% of 161 Analog Mini servos

Performance Analysis

Shaft Power	0.39–0.52 W
Power Density	0.673 W/in³ More power-dense than 37% of 158 Analog Mini servos
Torque Density	1.9328 oz-in/g Stronger than 54% of 77 Analog Mini servos
Torque-to-Volume Ratio	59.81 oz-in/in³ Denser torque than 71% of 77 Analog Mini servos
Speed-to-Weight	0.19099 (1/sec·g) Faster than 8% of 77 Analog Mini servos
Speed-Torque Trade-off	10.12 Better balanced than 92% of 77 Analog Mini servos
Torque Gain per Volt	18.12%/V More voltage-responsive (torque) than 86% of 58 Analog Mini servos
Speed Gain per Volt	8.34%/V More voltage-responsive (speed) than 9% of 58 Analog Mini servos
Voltage Range Width	1.2 V Wider voltage range than 67% of 88 Analog Mini servos