Redarc BCDC Alpha 50
#19 in 40 A and upFull review
For 4x4 and truck builds that need the toughest sealed charger with Bluetooth. Buyers on a budget get more amps per dollar elsewhere.
Amazon $735$735
2.6/5
For boats and vans where keeping the start battery charged matters as much as the house bank.
- 38 ACharge current
- NoSolar input
- 98%Efficiency
- 2 yearsWarranty
Check price at Amazon$381.65
Price checked October 31, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Bidirectional: keeps the start battery topped up from solar on the house bank
- Jump start mode charges a flat start battery from the house bank
- Turns on from alternator voltage, an ignition feed or engine vibration
- High efficiency keeps it cool under full load
Cons
- No solar input
- Only a 2 year warranty
- No Bluetooth; the remote is an extra cost
The Sterling Power BB12 family
Every Sterling Power BB12 model we rank, smallest first. Ratings compare each against its own current.
| Model | Charge current | Rating | Price |
|---|---|---|---|
| Sterling Power BB1225 25A | 24 A | 3.0/5 | $250 |
| Sterling Power BB1240 40A (this one) | 38 A | 2.6/5 | $381.65 |
| Sterling Power BB1270 70A | 60 A | 3.0/5 | $698 |
| Sterling Power BB12120 120A | 110 A | 3.4/5 | $763.30 |
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its current. How we rank explains each one.
Specifications
| Model number | BB1240 |
|---|---|
| Charging | |
| Charge current | 38 A |
| Input battery | 12 V |
| Output battery | 12 V |
| LiFePO4 profile | Yes |
| Smart alternator support | Yes |
| Peak efficiency | 98% |
| Solar | |
| Solar input | No |
| Build | |
| Bluetooth | No |
| Weight | 1.8 lb |
| Warranty | 2 years |
Alternatives in this current
Redarc BCDC Classic 50
#20 in 40 A and upFull review
For a big lithium bank in a 4x4 or truck where the charger must sit in the engine bay. Expensive for what it does.
Amazon $690$690
Redarc BCDC Classic 40 (BCDC1240D)
#22 in 40 A and upFull review
For overlanders who want a tough, potted charger that can live in the engine bay and take solar too. Buyers mounting inside the cabin can get similar charging for much less.
Amazon $620$620
Compare
Compare the Sterling Power BB1240 40A with any other DC-DC charger →
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