30 GW1812-N20 DC 12V (to 6V 3V) Micro Metal Slow Speed High Torque Worm Gear DC Motor Long Dual Shaft 16-381RPM Robot Eleltric Lock

Product Details

Gear Box Name: GW1812
Gear Box Type: Worm Gear
Motor Body Name: N20 (B1215)
Motor Body Type: DC Brushed Motor (BDC)
Rated Voltage: DC 12V (can be reduced to 6V, 3V, etc.)
Motor Weight: 12g (approx.)
Motor Size: 12mm(diameter) * 33mm(height)

It has 3 models which only different in shaft:

Model: GW1812-N20-S0308D (Short Shaft)

Shaft Number: Single
Shaft Size: 3mm(diameter) * 8mm(length)
Shaft Shape: D-Cut, 2.5mm(thickness) * 7.5mm(length)

Model: GW1812-N20-S0320D (Long Shaft)

Shaft Number: Single
Shaft Size: 3mm(diameter) * 20mm(length)
Shaft Shape: D-Cut, 2.5mm(thickness) * 19.5mm(length)

Model: GW1812-N20-D0310D (Double Shaft)

Shaft Number: Dual
Shaft Size: 3mm(diameter) * 10mm(length)
Shaft Shape: D-Cut, 2.5mm(thickness) * 9.2mm(length)

The motor's rated voltage is DC 12V, it can be reduced to 6V, 3V, etc. When the voltage is reduced, its speed, current and torque are reduced accordingly in proportion.

The Speed (RPM) in the purchase option is based on DC12V.
When the voltage is reduced to 6V, the speed is about 1/2 of those of 12V. So if you want a motor of 6V m RPM, please select 12V 2*m RPM, such as want 6V 100 RPM select 12V 200 RPM.
When the voltage is reduced to 3V, the speed is about 1/4 of those of 12V. So if you want a motor of 3V n RPM, please select 12V 4*n RPM, such as want 3V 50 RPM select 12V 200 RPM.

That is 12V 200RPM = 6V 100RPM = 3V 50RPM, and other RPM are calculated in the same way.

The No-load Speed at different voltage is (RPM):