Milwaukee has listed the M18 TOP-OFF 350W Power Supply and Charger, model 2856-20, as a coming soon product. It turns M18 batteries into a job site power source with a 350W pure sine wave inverter, and it is built to lock into the PACKOUT storage system.
What Milwaukee says it does
According to Milwaukee’s product page, the unit has two 120V outlets, one 100W USB-C PD port that works in both directions, and a 15W USB-C port. The pure sine wave output is aimed at sensitive electronics. It needs one M18 battery to run, and a second battery gives what the page calls 2x runtime.
The same unit also works as a charger. Milwaukee says it charges M18 batteries one after another through the included 65W wall adapter and USB-C cable. It has a carrying handle and a PACKOUT locking base, so it can ride on a stack of boxes. The page gives no charging times, weight or dimensions.
Price and timing
Milwaukee’s page shows no price and no date, only a Notify Me sign up. Power Tools Insider reported on August 20, 2026 that the MSRP is $269 and that the unit ships in February 2027. That price is stated in dollars without a country, and no Canadian price, retailer or date has been announced. Treat it as a US figure until Milwaukee Canada lists the product.
Power Tools Insider also says the unit has dual battery hot swap, so a dead pack can be replaced without interrupting power, and a display for real time load and pack level. It describes the 350W model as the first big jump in the TOP-OFF line and says it sits below the larger ROLL-ON units. Milwaukee’s own page does not list hot swap, so confirm it when the retail listing goes live. Power Tools Insider notes that runtime figures and the exact charging current to the packs have not been published.
Who it suits
- Tradespeople on the M18 platform: it uses packs you already own and rides with your PACKOUT boxes. Check the final runtime before you rely on it for a full shift.
- Electricians and finish crews: the pure sine wave output suits sensitive electronics, but check your tool’s wattage against the 350W limit.
- Serious DIYers: it can keep phones and a laptop alive in a garage or on a deck. Check whether you already own spare M18 batteries, because none come with the unit.
- Crew buyers: one unit per truck is simple, but wait for Canadian pricing and warranty terms.
What to check before you buy
Add up the wattage of what you plan to plug in, remember two batteries are needed for the longest runtime, and watch for a Canadian listing. The winter months ahead are a good time to plan, since the unit does not ship until February 2027.
