Overview The Black Box SP365A-R2 is a data surge protector designed specifically for RJ-11 telephone lines, providing essential protection against voltage spikes for communication devices. It features a 240 volt clamping circuit and can handle surges up to 75 amps, making it a reliable choice to protect fax machines, telephones, dial-up modems, and point-of-sale terminals from unexpected electrical damage. Its low shunt capacitance ensures that voice calls remain clear and data connections maintain their speed without interference. Key features 240 volt clamping voltage that quickly limits damaging electrical spikes to protect connected devices Surge handling capacity of up to 75 amps to absorb high-energy surges from lightning or power irregularities RJ-11 interface with four-wire pass-through design for easy installation without re-terminating cables Low shunt capacitance that preserves the clarity of voice calls and the integrity of data transmissions Compatible with a variety of devices including fax machines, telephones, dial-up modems, and POS terminals Compact housing that fits discreetly behind desks or inside wiring closets to minimize clutter CE approval ensuring compliance with recognized safety standards for peace of mind in professional and home environments Key specs Clamping voltage: 240 volts Surge current rating: 75 amps Interface type: RJ-11 with four-wire pass-through Shunt capacitance: low (exact value not specified) Approval: CE certified Connectivity and compatibility This surge protector supports four-wire RJ-11 telephone lines, making it suitable for both single-line and multi-line telephone systems. Its pass-through design shields the two active signal conductors while allowing easy connection to existing wiring without modification. This makes it a practical solution for offices, retail stores, call centers, and home workspaces that rely on uninterrupted phone or modem service. Installation and setup Installation is straightforward and requires no special tools or rewiring. Simply connect the cable from the wall jack to the protector’s female RJ-11 port, then attach your device to the male lead. The compact form factor allows it to be placed conveniently behind desks or inside wiring closets without taking up much space or creating clutter. Ideal uses and environments The SP365A-R2 is well suited to environments where telephone and modem lines are critical, such as small offices, retail counters, call centers, and home offices. It protects communication equipment from power surges that could cause downtime or damage, ensuring reliable operation in areas prone to electrical disturbances or lightning strikes.