US Automatic Sentry 300
#5 in Single swingFull review
A commercial grade, UL 325 listed single gate opener with a long warranty for buyers who value proven parts support over capacity per dollar.
Amazon $1,395$1,395
3.0/5
A budget, UL 325 listed kit for a short, light single gate. Anything over 12 ft or 300 lb needs the MM371W or larger.
- 300 lbGate weight
- 12 ftGate length
- Battery, solar readyPower
- 1 yearWarranty
Check price at Amazon$262.99
Price checked November 2, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- The lowest price of any UL 325 listed opener here, for a light farm or ornamental gate
- Runs from a battery, so the gate still works through a power cut
- Can go solar later with a 10 W Mighty Mule panel
Cons
- Only for gates up to 12 ft and 300 lb, so most driveway gates need a bigger model
- The battery is required and sold separately, adding to the cost
- The slowest opener here at about 18 seconds
- One year warranty
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its gate type. How we rank explains each one.
Specifications
| Model number | MM271 |
|---|---|
| Gate | |
| Gate type | Single swing |
| Heaviest gate | 300 lb |
| Longest gate | 12 ft |
| Time to open | 18 s |
| UL 325 listed | Yes |
| Power | |
| Power | Battery, solar ready |
| Motor voltage | 12 V |
| Build | |
| Remotes included | 1 |
| Weight | 16 lb |
| Warranty | 1 year |
Alternatives in this gate type
Blütezeit MS600 Solar Swing
#6 in Single swingFull review
A tidy all in one solar kit for a heavy single gate away from power, with a longer warranty than most budget brands.
Amazon $569.99$569.99
JUJIANG C026 Solar Single
#8 in Single swingFull review
A complete solar kit for a remote single farm or ranch gate on a budget. Its safety listing and duty rating are not published.
Amazon $369.99$369.99
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