PowerSmart B8721S1 Self-Propelled
#14 in Self-propelledFull review
A low cost rear wheel drive mower with a name brand engine, for sloped lawns up to a third of an acre that you bag or mulch.
Amazon $389.99 PowerSmart $379.99$379.99
3.3/5
A low cost self propelled mower for lawns up to about a third of an acre, best if you already own Greenworks 40V tools.
- 21 inDeck
- 40 V, 5 Ah of batteryPower
- Rear-wheel driveDrive
- 3 yearsWarranty
Check price at Amazon$465.99
Price checked October 31, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- One of the cheapest self propelled 21 in kits from a major brand
- Steel deck with mulch, bag, side discharge and a turbo leaf pickup mode
- Folds flat for storage in a small shed or garage
Cons
- The 5.0Ah battery runs about 40 minutes, about a third of an acre
- Three year warranty, shorter than EGO’s five years
- The cutting height tops out at 3.6 in, low for long summer grass
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its drive. How we rank explains each one.
Specifications
| Model number | MO40L517 |
|---|---|
| Cutting | |
| Deck width | 21 in |
| Deck | Steel |
| Cutting height | 1.2 to 3.6 in, 7 positions |
| Bag | Yes |
| Mulch | Yes |
| Side discharge | Yes |
| Power | |
| Power | Battery |
| Engine or battery | 40 V, 5 Ah of battery |
| Battery energy | 200 Wh |
| Battery included | Yes |
| Runtime | 40 min |
| Brushless motor | Yes |
| Build | |
| Drive | Rear-wheel drive |
| Folds upright | Yes |
| Weight | 61.7 lb |
| Warranty | 3 years |
| Battery warranty | 3 years |
| Released | 2024-01-20 |
Alternatives in this drive
EGO LM2135SP Select Cut
#15 in Self-propelledFull review
EGO’s best known 21 in self propelled mower, for half acre lawns where you want Touch Drive and blade choice. The cheaper LM2114SP cuts much the same grass.
Amazon $749$749
Toro Recycler 22 in FWD 21445
#17 in Self-propelledFull review
A 22 in Toro for flat to gently sloped half acre lawns where storage space is tight. Choose the rear wheel drive models for hills.
Toro $499$499
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