The Merlin C840 is compatible with the Merlin Security+ series, allowing keyless entry via 4-digit code access.
Compatible with:
MJ3800BBU, MT800, MT600, MT1000, MT3850, MT5580P, MT60P, MT60, MT230, RollerAce (MR60), MR600, MR800, MR1000, MJ3800, MJ3800R