These are high quality sealed Double Pole - Double Through (DPDT) relays. This relay's coil is rated for 5V. The nominal operating current is 80.6mA so it will need additional circuity to close the relay with a microcontroller like an Arduino or SBC such as a Raspberry Pi or BeagleBone Black.
These are high quality sealed Single Pole - Double Through (SPDT) relays. This relay's coil is rated for 5V.
SparkFun's minimal design approach to Arduino. This is a 5V Arduino running the 16MHz bootloader.
This is an Enclosed 4-wheel drive remote control robot kit. It uses four powerful wheelchair motors and the inside robot cavity has plenty of room for electronics.