PingZheng 1.9g micro digital servos PZ040120，PZ15330 is the previous code of manufacture，it use 0412 coreless motor,so  more powerful than 2.2g servos about 50g of torque.

Size:13.5x6.2x20mm

Weight: 1.9g
Speed: 0.06s/60°3.7V   0.04s/60°4.2V
Torque: 0.15Kg/3.7V 0.17Kg/4.2V
Bearing: no
Wire length: 110mm
Votage: 2.5-4.8V

SH1.0mm JST and GH1.25mm JST pitch plug version

The same arm with 1.7g servos

The actual weight is about 2.2g.