Designed to accept and connect wires and utilizing a variety of clamping methods in a centralized location, terminal blocks come in a variety of shapes and sizes. Used heavily in the industrial and transportation markets, but also found in many other sectors including telecom and instrumentation, terminal blocks are available in a variety of termination styles with selection based totally on application. Typical applications for terminal blocks include proximity sensors, power supplies, HVAC systems, rail systems signaling, and infrastructure and process plant instrumentation connections. Industry standards associated with terminal blocks include Mil-T-55164/A-A-59125, UL/CSA/IEC, NEMA, and DIN. Terminal block styles include barrier blocks, sectional blocks (modular), PCB-mounted blocks, power blocks, and specialty-type blocks.