This Ignition Electrode is compatible with Morco GB24 and GB30 series boilers, including models GB24, GB24 SI, GB24 SII, GB24 SII Erp, GB24 SIII, GB24 IV, GB30, GB30 SI, GB30 SII, GB30 SII Erp, GB30 SIII, and GB30 IV. The part number is ICB306001. If you are unsure about compatibility, please contact the Hanicks Heating & Spares Tech Team at 01302 279234 with your boiler's GC Number.