M18 FUEL SAWZALL Reciprocating Saw w/ ONE-KEY (Tool Only)
Battery answer
Every reviewed M18 pack powers SKU 2721-20 at full rated performance, with no battery-specific condition.
- Battery platform
- Milwaukee M18
- Packs required
- Not published by Milwaukee
- 9 work without conditions.
Battery requirement sources (1)
- Milwaukee Tool — manufacturer page, retrieved 2026-07-31
Compare the reviewed packs See tool specifications and sources
Milwaukee · Reciprocating Saws · SKU 2721-20 · Milwaukee source
Compare the reviewed M18 packs
| Battery | Capacity | Energy | Power level | Answer |
|---|---|---|---|---|
| 48-11-1813 | 12 Ah | 216 Wh | PWR5 | Works |
| 48-11-1820 | 2 Ah | 36 Wh | not published | Works |
| 48-11-1828 | 3 Ah | 54 Wh | not published | Works |
| 48-11-1840 | 4 Ah | 72 Wh | not published | Works |
| 48-11-1850 | 5 Ah | 90 Wh | PWR2 | Works |
| 48-11-1850R | 5 Ah | 90 Wh | not published | Works |
| 48-11-1861 | 6 Ah | 108 Wh | PWR4 | Works |
| 48-11-1865 | 6 Ah | 108 Wh | PWR3 | Works |
| 48-11-1881 | 8 Ah | 144 Wh | PWR4 | Works |
Energy is capacity × nominal voltage — our arithmetic on Milwaukee’s figures, not a number they publish. It is the only honest way to compare packs across capacities. Power level is Milwaukee’s own PWR tier where they publish one.
Compatibility sources (1)
- Milwaukee Tool — manufacturer support, retrieved 2026-07-30“All M18 Batteries are compatible with M18 tools & chargers.”
Kit configurations
Ways Milwaukee sells this exact tool in a box. Contents are decomposed to manufacturer SKUs; non-SKU’d accessories — side handles, belt clips, cases — are omitted because they carry no compatibility meaning.
M18 FUEL SAWZALL Reciprocating Saw w/ ONE-KEY Kit (2721-22)
| Qty | Component | SKU |
|---|---|---|
| 1 | M18 FUEL SAWZALL Reciprocating Saw w/ ONE-KEY (Tool Only) | 2721-20 |
| 2 | M18 REDLITHIUM XC5.0 Extended Capacity Battery Pack | 48-11-1850 |
| 1 | M18 & M12 Multi-Voltage Charger | 48-59-1812 |
Battery capacity in the box: 10.0 Ah across 2 pack(s). This is the directly comparable capacity when weighing the kit against the bare tool plus packs.
Contents provenance: manufacturer claim; review completed 2026-07-31 by jon.
Contents sources for 2721-22 (1)
- Milwaukee Tool — manufacturer page, retrieved 2026-07-31
Tool specifications and manufacturer claims
Basic tool facts
| Weight, bare tool | Not published for this exact SKU |
|---|
Specification sources (1)
- Milwaukee Tool — manufacturer page, retrieved 2026-07-31
Full specifications
As published by Milwaukee for SKU 2721-20, read 2026-07-31. Values are quoted in their units, not reformatted.
| Tool Warranty | 5 Years |
|---|---|
| Power Source | Cordless |
| Length | 17-3/4" |
| Weight | 7.4 lbs |
| ONE KEY Enabled | Yes |
| Warranty | 5 Year Limited Warranty |
| LED Light | Yes |
| Stroke Length | 1-1/8" |
| Keyless Adjustable Shoe | Yes |
| Keyless Blade Clamp | Yes (QUIK-LOK Universal) |
| Blade Clamp | QUIK-LOK Universal |
| SPM | 0 - 3,000 |
| Hang Hook | Yes |
| Cut Brake | Yes |
| OneKey Compatible | Yes |
| Fuel | Yes |
| Voltage | 18V |
What Milwaukee says about it
- Delivers faster than corded cutting speed and the durability of a corded saw
- Powerstate brushless motor: supplies constant power for faster cuts and reduced heat for extended life
- REDLINK PLUS intelligence: provides optimized performance and overload protection using total system communication between tool, battery and charger
- 1-key compatible: customize, track and manage tool’s performance and location
- Easily toggle between up to 4 custom performance profiles that can be saved to the memory of the tool
- Universal keyless blade clamp: QUIK-LOK universal clamp accepts all reciprocating saw blades with a concealed, keyless clamp system
- Keyless adjustable shoe: adjustable show allows user to easily change position of shoe to extend blade life
- LED light: illuminates dark work spaces
- Hang hook: allows for convenient storage on the job
- Compatible with all M18 batteries and M18 chargers
Manufacturer marketing copy, reproduced so you can judge it. We have not tested these claims.