IGNITION COIL Module fits Lawn-Boy M21ZPR M21ZPRA M21ZPRB M21ZPRC M21ZPRD MowersOne New Aftermarket Replacement Ignition Coil Module for Lawn Boy Walk Behind Mowers This ignition coil module (armature magneto) is a direct replacement for Lawn Boy Silver and Gold Series 2 stroke walk behind lawn mowers. The coil generates and delivers high voltage current to the spark plug as the flywheel rotates, enabling reliable ignition and engine starting. A faulty or worn ignition coil is a common cause of no spark and hard starting