Battery Tender
Battery Tender Plus (021-0128)
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Best Car Battery Chargers · head-to-head
Battery Tender Plus (021-0128) vs Digital 1200
A sourced, side-by-side comparison. Battery Tender Plus (021-0128) is cheaper at —. Every spec and price links to its source.
OPTIMA
Digital 1200
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Full spec sheet
✓ marks the stronger figure where "more" — or "less", for price and weight — is unambiguously better.
| Spec | Battery Tender Plus (021-0128) | Digital 1200 |
|---|---|---|
| US price | — | — |
| Brand | Battery Tender | OPTIMA |
| Released | — | — |
| Max charge amps | 1.25 | 12 |
| Voltage support (V) | 12 | 12 |
| Battery chemistry | Flooded, Sealed/GRT (Gas Recombinant Technology), and AGM 12V lead-acid batteries | AGM and Flooded 12V lead-acid batteries, including OPTIMA RedTop/BlueTop/YellowTop and standard automotive/marine/motorcycle batteries |
| Modes | Fully automatic 4-step charging: bulk charge, absorption, and adaptive float/maintenance (ISM) | 6-stage fully automatic charging; Charging Quick-Set Selector (Engine Start/Aging, 12V High-Performance AGM, 12V Standard Flooded & AGM, Motorcycle/Auto/Marine) plus a separate Maintainer Quick-Set Selector (Battery Maintainer, Aux Maintainer up to 4A) |
| Waterproof rating | — | — |
| Reverse polarity protection | — | Yes |
| Display | 3-LED indicator (red = bulk charging, flashing green = absorption, solid green = float/complete) | Circular backlit LCD gauge (Volts DC, Amps DC, charge-stage text) with an LCD-backlight toggle |
| Temperature compensation | — | Yes |
Sources — Battery Tender Plus (021-0128): manualslib.com (verified 2026-08-01). Digital 1200: manualslib.com (verified 2026-08-01).
What's the difference between the Battery Tender Plus (021-0128) and Digital 1200?
Where the two actually differ on the specs we track (4 of 8). Matching specs are omitted.
- Max charge amps: Battery Tender Plus (021-0128) 1.25 vs Digital 1200 12
- Battery chemistry: Battery Tender Plus (021-0128) Flooded, Sealed/GRT (Gas Recombinant Technology), and AGM 12V lead-acid batteries vs Digital 1200 AGM and Flooded 12V lead-acid batteries, including OPTIMA RedTop/BlueTop/YellowTop and standard automotive/marine/motorcycle batteries
- Modes: Battery Tender Plus (021-0128) Fully automatic 4-step charging: bulk charge, absorption, and adaptive float/maintenance (ISM) vs Digital 1200 6-stage fully automatic charging; Charging Quick-Set Selector (Engine Start/Aging, 12V High-Performance AGM, 12V Standard Flooded & AGM, Motorcycle/Auto/Marine) plus a separate Maintainer Quick-Set Selector (Battery Maintainer, Aux Maintainer up to 4A)
- Display: Battery Tender Plus (021-0128) 3-LED indicator (red = bulk charging, flashing green = absorption, solid green = float/complete) vs Digital 1200 Circular backlit LCD gauge (Volts DC, Amps DC, charge-stage text) with an LCD-backlight toggle