This also allowed for cost savings, as the reels could be used twice. The cables were spun using air spinning with controlled tension, which allowed spinning with little space and with a crew with limited spinning experience.[25] This involved installing a carrier which shuttles forward and back over the catwalk; it spins the upper side of the cable in the one direction and the lower side in the other direction. The system has two reel racks, each with four reels of wire. Each rack only uses one reel at a time, allowing for minimum down-time when changing reels. Wires were connected using pressure casing. The balance in the system is kept in place using a counterbalance tower