CY Screw Clamp Terminal Blocks Altech CY Screw Clamp Terminal Blocks offer a variety of design options and meet global standards. The components feature snap-on feed-through terminal blocks that easily snap onto a DIN rail. The series provides a universal push-in jumper system with jumper channels for any jumper combination. Altech CY terminal blocks are ideal for use in machines, control and automation, and power distribution applications.