Makita 421850-4 Spare Part - DUST PLATE HM1800/HM1810
Original Makita 421850-4 — Dust Plate (front nose seal) for demolition hammers. This is the original Makita dust plate designed to sit at the tool’s front/nose and block concrete dust and grit from entering the striker chamber, helping protect seals and reduce premature wear.
Made from a tough, flexible elastomer, the plate conforms around the nose while resisting tearing under heavy vibration and repeated impact — restoring the original dust barrier and helping keep the hammer running smoothly. Replacement of this part is a common service item on breakers used in masonry and concrete work.
Fits Makita HM1800 and HM1810 series demolition hammers, so it’s the correct spare when you’re repairing these tool ; the HM1810 uses a 28.6 mm (1-1/8") hex shank bit.
If you’re ordering Makita spare parts for a repair, this 421850-4 dust plate gives the correct fit and material spec to return the nose seal to original condition — simple to install during routine service or strike-group rebuilds.
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Compatible models this part will fit:
