The most popular range in the STX series offering, the Surge-Trap® type 1 STXR meets requirements for UL1449 Fourth Edition and is ideal for the replacement of obsolete surge arrestors. The STXR series SPD feature TPMOV® technology inside making them the safest product available. With a small, compact design and line or load installation flexibility the STXR series is the perfect fit for branch panel and/or individual equipment protection.