590044201 Blade Adapter - for Husqvarna Lawn Mower LC221A LC221R L221A LC221A LC221AH LC221RH L421P L221AK L221AHK L321AH L321AHE

What It Is

The Husqvarna 590044201 Blade Adapter is the stamped steel hub that connects the mower blade to the engine crankshaft on select Husqvarna walk-behind mowers. It is designed for residential use on models with a 21-inch or 22-inch stamped steel deck.

Fitment & Compatibility

Check these before buying:

• Model list: Fits Husqvarna LC221A, LC221R, L221A, LC221A, LC221AH, LC221RH, L421P, L221AK, L221AHK, L321AH, L321AHE. If your model isn’t listed, verify the crankshaft shape—this adapter is for a 5-point star pattern (not a single D-hole or keyed shaft).
• OEM vs aftermarket: This is an OEM Husqvarna part. Aftermarket adapters may use cheaper steel or looser tolerances, which can cause blade wobble or vibration.
• Deck size: Works with 21-inch and 22-inch decks only. Do not use on larger decks.
• Center hole: 1-inch diameter. Measure your blade’s center hole—if it’s 7/8-inch, this adapter won’t fit.
• Quantity: You get one adapter. Most mowers need only one.

Key Things to Know

• Installation difficulty: Easy. Remove the blade bolt, swap the old adapter, torque the new one to 35-45 ft-lbs. Use a block of wood to lock the blade.
• Common gotcha: The adapter can corrode or warp over time. If your blade won’t sit flat or the mower vibrates excessively, the adapter is likely bent—replace it immediately.
• Quality: Stamped steel, not cast. Adequate for residential use, but not as durable as a forged adapter. Expect 3-5 years of normal use.
• Bolt not included: You’ll need the original blade bolt or a replacement (M10x1.25, about 30mm long).

Should You Buy It

Buy this if your Husqvarna model is on the list, the old adapter is visibly bent or rusted, and you want an exact OEM replacement with no guesswork. Skip it if you have a different crankshaft shape or a larger deck—you’ll need a different adapter.