This is a supplied-together kit, not a bare relay: a WRU-10 RAL self-reclosing earth leakage relay with its Ø28 mm built-in toroidal transformer, packaged with an 85 A contactor as the switching element. The pairing is what makes the assembly work. An earth leakage relay measures and decides but cannot break current itself; it needs a switching device sized for the circuit. Supplied as a kit, the contactor is already matched to the relay's output and rated at 85 A, so the reclosing sequence has something able to open and re-close the load repeatedly without the specifier having to size and verify that pairing themselves. Automatic reclosing restores supply after a transient earth fault and locks out on a persistent one — the behaviour wanted on unmanned sites where an attendance costs more than the outage. Sensitivity and delay are adjustable. It is a type A device: it responds to sinusoidal AC residual currents and to pulsating DC residual currents. Circutor specify it as superimmunised, with high-frequency filtering and true RMS (TRMS) measurement, so that the harmonic leakage normal in an installation full of switch-mode loads does not read as a fault. Manufactured by Circutor (Spain) and supplied under the Function brand; the Circutor catalogue reference is WRU-10 RAL. Supplied by cBallast on quote-to-invoice terms; lead time and freight are quoted per RFQ against the destination Incoterm.