# Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only) vs Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only): specs and price compared

A sourced, side-by-side comparison of the Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only) (Milwaukee) and Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only) (Ryobi) among angle grinders. Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only) is the cheaper of the two at $49.97.

## Side by side

| Spec | Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only) | Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only) |
| --- | --- | --- |
| US price | $229 | $49.97 |
| Brand | Milwaukee | Ryobi |
| Disc size (in) | 5 in | 4.5 in |
| Power source | cordless | cordless |
| Amps or voltage | 18 V | 18 V |
| Max (rpm) | 8500 | 6500 |
| Brushless | Yes | No |
| Switch type | paddle | trigger |
| No volt release | — | — |
| Weight (lb) | 3.1 | 4.8 |

## Key differences

- Disc size (in): Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only) 5 in vs Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only) 4.5 in
- Max (rpm): Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only) 8500 vs Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only) 6500
- Brushless: Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only) Yes vs Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only) No
- Switch type: Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only) paddle vs Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only) trigger
- Weight (lb): Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only) 3.1 vs Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only) 4.8

## What reviewers say

**Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only)** — Only one whitelisted tester, Pro Tool Reviews, covers the exact 2880-20, and only inside a Milwaukee lineup comparison rather than a standalone bench test. Editors endorse its runtime and safer paddle-switch design, but every performance figure (135 rebar cuts, 11A, 8,500 RPM, $199) is Milwaukee's own claim, not independently measured. (1 sourced review.)

## Sources

- Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only): https://www.milwaukeetool.com/products/details/m18-fuel-4-1-2-5-braking-grinder-paddle-switch-no-lock/2880-20 (milwaukeetool.com, verified 2026-06-20)
- Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only): https://www.ryobitools.com/products/33287139576 (ryobitools.com, verified 2026-06-20)

Canonical: https://frontdeskreview.com/gear/angle-grinders/milwaukee-2880-20-vs-ryobi-p421/
Cite: Per The Front Desk Review, Milwaukee M18 FUEL 2880-20 4-1/2 in./5 in. Grinder Paddle Switch No-Lock (Tool Only) ($229) vs Ryobi P421 18V ONE+ 4-1/2 in. Cordless Angle Grinder (Tool Only) ($49.97) — sourced spec-by-spec comparison at https://frontdeskreview.com/gear/angle-grinders/milwaukee-2880-20-vs-ryobi-p421/
License: CC BY 4.0.