Craftsman CMCG400B (V20 Cordless 4-1/2 in. Small Angle Grinder, Tool Only)

By Craftsman · Angle Grinders · Power Tools

  • V20 cordless, brushed motor
  • Wheel 4-1/2 in
  • 8,500 RPM
  • Weight about 6.2 lb
  • Warranty 3 years limited

Lowest price seen
~$69.00 (approx.)
from $69.00 at Amazon

Prices are snapshots. Check the current price with the store.

Summary

A budget cordless 4-1/2-inch angle grinder for people already on Craftsman’s V20 battery platform. The one thing to check before buying: it runs a brushed motor, not the brushless design of Craftsman’s newer V20 grinders.

Strengths

  • One of the least expensive cordless angle grinders on a major US battery platform.
  • Cast metal gear housing that Craftsman says dissipates heat in extended use.
  • 3-position side handle, tool-free guard and spindle lock make it easy to handle and set up.
  • Runs on the whole V20 battery lineup, including the 2026 ADVANCED packs.
  • A 3-year limited warranty is competitive for this class.

Weaknesses

  • Brushed motor, while Craftsman’s newer V20 grinders are brushless with up to 65% more power.
  • Sold bare: the battery and charger are separate purchases, which pushes the total cost up.
  • Weight is missing from the Craftsman product page; the 5 lb figure comes from a retailer spec sheet.
  • No instrumented test data and no failure-rate data exist for this model.

Verified specifications

ModelCMCG400B, tool only — battery and charger sold separately.
PlatformCraftsman V20* (20V Max, nominal 18V).
Motorbrushed, not brushless.
No-load speed8,500 RPM.
Wheel diameter4-1/2 in (114.3 mm).
Gear housingcast metal, which Craftsman says dissipates heat during extended use.
Side handle3-position.
Guardtool-free adjustment.
Spindle lockyes.
Switchtrigger.
Variable speedlisted as yes on the RONA spec sheet, but Craftsman’s product page does not mention it — unconfirmed.
Weightabout 5 lb per the RONA spec sheet; the Craftsman product page does not state weight.
Battery compatibilityall V20 batteries (2.0Ah, 4.0Ah, 6.0Ah, 9.0Ah, and the 2026 ADVANCED 3.0Ah and 6.0Ah packs).
Warranty3-year limited.
In the boxgrinder, grinding guard, grinding wheel, spanner wrench.
Full research notes and sources

Which model this is

The CMCG400B is the older brushed grinder on Craftsman’s V20 platform, which launched in 2018. The newer brushless V20 grinders are the CMCG450B, CMCG451B and CMCG452B; the kit version of this grinder, with battery and charger, is the CMCG400M1. Do not confuse it with the corded CMEG100 and CMEG200.

The US Amazon listing for this model is ASIN B07MFD6N3L.

Battery platform and total cost

The tool sells bare at $69 from Lowe’s, Acme Tools and Ace Hardware. A V20 battery and charger kit is a separate purchase, typically $50–100 or more depending on retailer and promotions, so a buyer new to the platform can see the total approach or exceed the brushless alternatives. The kit version CMCG400M1, with a 4.0Ah battery and charger, is $189 at Acme Tools. Craftsman’s new ADVANCED battery kits — 3.0Ah at $139 MSRP and 6.0Ah at $199 MSRP (Craftsman, May 2026) — work with all V20 tools.

Brushed motor versus brushless

Craftsman says its newer brushless V20 grinders deliver up to 65% more power, and the company’s own comparison for the brushless CMCG450B uses the brushed CMCG400M1 kit as its baseline. A brushed motor may be a durability concern next to a brushless one, but nobody has published a failure rate for this model. No instrumented professional test of the CMCG400B exists either; the only independent coverage found is a YouTube review.

Owner experiences, warranty and repairs

Owner sentiment across major retailers is generally positive, with praise for value for money, ergonomics, the 3-position handle and V20 compatibility. One Lowe’s reviewer of the kit version CMCG400M1 reports it died after about three years of intermittent use — one person’s experience, not a failure rate.

Craftsman backs the tool with a 3-year limited warranty, shown as 36 months parts and labor on the RONA spec sheet. Customer service is available at 888-331-4569, seven days a week, 7 AM to 11 PM ET. No parts-availability information was found for this model. A Garage Journal forum discussion notes that corded grinders suit heavy, continuous work while cordless is better for quick tasks — general advice, not specific to this tool.

Is it worth it?

If you already own V20 batteries, $69 makes this a cheap way into cordless grinding. If you do not, the battery and charger can push the total close to the brushless competition — the CMCG452B is listed at $99 at Acme Tools, down from $129.99. For heavy or frequent use, the brushless models may offer better long-term value; for light DIY jobs, the brushed CMCG400B at its price is a reasonable buy.

Sources

Manufacturer:

Independent reviews:

Owner reports:

Retailer listings:

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