The 28BYJ48 Uni-polar 5VDC 5-Pin stepper motor requires a ULN2003 Motor Driver if it is to be used with a microcontroller such as the Arduino.
Specifications:
Rated Voltage: DC5V 4-phase
Step angle: 5.625 x 1/64
DC Resistance: 200Ω±7% (25C)
Insulation Resistance: >10MΩ (500V)
Dielectric Strength: 600V AC / 1mA / 1s
Insulation Grade: A
No-load Pull in Frequency: >600Hz
No-load Pull out Frequency: >1000Hz
Pull in Torque: >34.3mN.m(120Hz)
Detent Torque: >34.3mN.m