Spring cage terminal blocks are gaining attention because of their top-entry, speed of termination and push-in bridging systems. The wiring technician has a view of the connection points and the wire ducts can be positioned very close to the rail assemblies. If the screw clamp is not torqued with a power screwdriver, the spring cage is about 10-15% faster. A push-in style jumper is typical and if a dual channel design is chosen, you have a very flexible system to handle chain and multi-position bridging. This results in a lower installed cost.