No. DeWalt 20V MAX/FlexVolt batteries and Bauer 20V batteries are not interchangeable, and there is no shared corporate parent to blame for the confusion — these are simply two unrelated companies that both happened to build a “20V” cordless platform.
It is worth clearing up who actually makes Bauer, because a lot of people assume it is some independent third-party brand competing with DeWalt on store shelves. It isn’t. Bauer is Harbor Freight’s own house brand. Harbor Freight’s own newsroom says as much directly, describing a new combo kit added “to its…customer-favorite BAUER™ line.” DeWalt, meanwhile, is a Stanley Black & Decker brand. That is the whole ownership picture: one retailer’s private label on one side, one large tool manufacturer’s flagship brand on the other, with nothing connecting them.
Each brand’s own pages describe only their own hardware. DeWalt’s FLEXVOLT Battery System page states that “FLEXVOLT batteries are compatible with DEWALT 20V MAX power tools” — full stop, no mention of Bauer or anything else. Harbor Freight’s own BAUER 20V 5 Ah battery page mirrors that self-contained framing: “Works with all BAUER™ 20V cordless tools,” and separately, “This dependable BAUER™ lithium-ion battery fits all your BAUER™ 20V cordless tools.” Two platforms, two closed loops, and neither one acknowledges the other exists.
Bauer’s own product pages are also fairly specific about how big that closed loop is, even if the two numbers don’t quite agree. The BAUER 20V Cordless 1/2 in. Drill/Driver Kit page invites shoppers to “shop our 20V Bauer power tools system with over 65 compatible products,” while a Harbor Freight newsroom release from August 2024 puts the same lineup at “over 70 products.” Neither figure is wrong — they’re just two real snapshots from two different pages at two different times, and the lineup has clearly kept growing between them. Either way, that drill/driver kit itself is a decent stand-in for what “Bauer 20V” means in practice: a 1/2 in. all-metal keyless chuck, a two-speed selector rated at 450/1700 RPM, 450 in-lbs of torque, sold with a 20V 1.5 Ah battery and charger — a complete, self-supporting tool system with its own spec sheet, not an accessory line built to slot into somebody else’s batteries.
DeWalt’s side of the story adds one more piece of nuance, though it’s a nuance about DeWalt alone. DeWalt’s DCA1820 adapter page notes that “maximum initial battery voltage (measured without a workload) is 20 volts,” while “nominal voltage is 18” — meaning 20V MAX is really an 18V-class platform once you look past the marketing number on the box. That’s useful context for understanding DeWalt’s own naming, but it isn’t a bridge to Bauer. No Bauer page states a comparable nominal-vs-peak figure for its own 20V batteries, so this guide isn’t going to manufacture a voltage-class comparison that Bauer’s own spec sheet doesn’t support.
Practical takeaway
If you’ve got Bauer tools from Harbor Freight, stay in the Bauer 20V battery and charger family; if you’ve got DeWalt 20V MAX or FlexVolt tools, stay with DeWalt’s own batteries and chargers. Unlike the DeWalt-and-Craftsman situation on this site, there’s no shared parent company here muddying the waters — Bauer answers to Harbor Freight, DeWalt answers to Stanley Black & Decker, and neither one designed its battery to fit the other’s tools. Both brands slapping “20V” on their packaging is a marketing coincidence, not a compatibility claim from either company, so don’t let the matching number talk you into cross-shopping batteries.
How this was checked
Facts on this page are drawn from DeWalt’s own FLEXVOLT Battery System and DCA1820 Adapter pages, Harbor Freight’s own BAUER 20V battery and drill/driver kit product pages, and a Harbor Freight newsroom press release.
Sources checked: 2026-08-17. A new review date will only be set after the linked pages are re-checked.