S4
Rated for 0.25 acres and 42% grade — that is 22.8°, not 42°. On a real lawn, once you allow for borders and travel paths, plan on about 0.2 acres.
Rated area0.25 acres
Max grade42% · 22.8°
Drive2WD
Navigation3D LiDAR + AI vision
Sold viaOnline retail
What it handles
Two-wheel drive, which caps how steep it can work. That is a flat-to-gently-rolling rating — a real slope will stall it.
Navigation includes vision or LiDAR, so it keeps working under tree cover where satellite-only machines lose their fix.
Below a quarter acre once the coverage buffer is applied — too small for any of our acreage bands.
If your ground is steeper
These are rated for a similar area but hold more grade than the S4’s 42%.
Mammotion LUBA 3 AWD 15000.37 ac · 80% · AWD
Mammotion LUBA mini 20.25 ac · 80% · AWD
Mammotion LUBA mini AWD 800H0.2 ac · 80% · AWD
ANTHBOT M90.25 ac · 45% · 2WD
How confident we are
Cross-checked against the manufacturer and at least one other source.
Slope filled: 42% (Sunseeker prints 22 deg; exact conversion is 22.8). Area 0.25 acre confirmed - US copy says 10,890 sq ft, metric copy 1000 sq m. Rear-wheel drive, which is why it sits far below the AWD X7.