Milwaukee M12 HACKZALL (2420-20) review

A basic M12 HACKZALL with its own operating profile

The Milwaukee 2420-20 is the M12 HACKZALL reciprocating saw, a compact one-handed cordless model distinct from the later M12 FUEL 2520-20. The exact U.S. product page lists one 2420-20 saw in the box. Its operator manual identifies a 12V M12 battery system, variable-speed trigger, work light and Quik-Lok blade clamp. The manual's specifications give 0–3,000 no-load strokes per minute and a 1/2-inch stroke. These are useful identification points, not a prediction of cutting speed in a particular material.

The exact manufacturer page describes an 11-inch form and calls the saw compact and lightweight. Its weight text is internally inconsistent: the product overview says 2.6 lb, while a feature bullet says 2.2 lb, and neither statement clarifies the battery basis. The archived manufacturer category card also lists 2.62 lb excluding battery, but that does not resolve the direct-page conflict. I leave the bare-tool weight unknown instead of choosing the most favorable number. A strict maximum-weight filter cannot certify the model from these conflicting statements.

Package identity and platform fit

The 2420-20 product page's in-box list contains one M12 HACKZALL saw and no battery or charger. Milwaukee also has distinct 2420-21 and 2420-22 kit pages listing battery, charger and additional contents. Those other suffixes are not part of this 2420-20 tool-only assessment. Check the exact model number when comparing a seller's box list; a product photo or family overview should not be used to assume the kit battery count or included blades.

The M12 platform is a practical fit only when it matches batteries and chargers the buyer owns or intends to acquire. The 2420-20 is not an M18 HACKZALL and cannot use an M18 battery simply because both models come from Milwaukee. The 2520-20 FUEL saw is also a different machine: its manual lists a longer 5/8-inch stroke, and its exact product page describes a POWERSTATE brushless motor, features not established for the 2420-20. That is a comparison of published facts, not an independent power or durability verdict.

Blade changes, length and supported work

The 2420-20 manual states that the Quik-Lok clamp accepts 1/2-inch universal HACKZALL and SAWZALL blades. It specifies a minimum blade length of 3-1/2 inches and says the blade needs to extend beyond the shoe and work through the full stroke. For a blade change, the manual instructs the user to remove the battery, twist the clamp collar, seat the blade, allow the spring-loaded mechanism to clamp it and tug the blade to verify it is secure. The manual also recommends keeping the clamp clean; debris can interfere with blade retention.

The shoe is identified in the manual, and a cutting procedure describes using its edge as a pivot during a plunge cut. That operating instruction does not establish an adjustable shoe or indexed shoe positions. The sources reviewed do not establish selectable orbital action either. The manual says to hold the shoe flat against the work for general cutting, support the stock and check the area for hidden gas, electrical and water lines before blind or plunge cuts. Use the correct blade for the job and follow the full safety guidance rather than infer control features from the HACKZALL name.

Who may prefer the 2420-20

This model is a reasonable research candidate for someone who specifically wants a compact one-handed saw for M12 and already has the relevant power equipment, or who will source it separately. The tool-only box avoids paying for duplicate battery and charger equipment, but that is not an overall cost claim; it also leaves the buyer responsible for compatible power components. The older 1/2-inch stroke and brushed/unspecified motor field distinguish this record from the documented FUEL 2520-20 but do not establish which saw is faster or more reliable.

Look elsewhere in the assessed library if you need a verified bare-tool weight, an adjustable shoe, a selectable orbital mode, or a kit whose exact battery and charger parts are listed in the same package. The exact product page gives contradictory weight figures, and its box list is only the saw. This review is based on Milwaukee's current 2420-20 U.S. product page and its exact 2420-20 operator manual, with the manufacturer category card used to check and record the weight conflict. The saw was not owned, tested or measured for this article; there is no hands-on cutting, runtime or durability claim.

Milwaukee 2420-20 product page · 2420-20 operator manual