These chunky block servos integrate neatly with axles and blocks from popular ABS stud-based building block construction kits! We like how you can connect two axles to the dual outputs on this servo so you can power two wheels or gears, or mount the servo securely inside articulated limbs and other contraptions. It's also easy to connect blocks to the sides by poking the studs into the holes. The gears inside these servos will 'slip' when the blocking load is too high instead of jamming - helping avoid damage to your servos and boards. The wires are a standard servo pinout - Red - positive Brown - negative Yellow - data The cable has a fused 1x3 female DuPont socket connector on the end, so it's easy to connect to jumper jerky or 0.1" pitch pin headers. LEGO® is a trademark of the LEGO Group of companies which does not sponsor, authorize or endorse this product.