Features
- Digital brushless motor
- Dual-function lock-switch with lock-on and soft-start
- Tool-less guard adjustment
- Onboard wrench storage for the wrench
- Removable dust screens for cleaning
- Includes 5.0 Ah PWRCORE 20 lithium battery
- Includes PWRASSIST USB adapter to power external devices
- Includes Auto PWRJUMP charger with quick-charge capability
Specifications
Brushless | Yes |
Disc Size | 4-1/2 in. |
No Load Speed | 8500 rpm |
Tool Height (Inch) | 4-1/8 |
Tool Length (Inch) | 12-1/8 |
Tool Weight (Pound) | 4.14 |
Tool Width (Inch) | 3 |
Voltage (Nominal) | 18 V |
Voltage (V Max) | 20 V |
Battery Capacity | 5.0 Ah (PWRCORE 20) |
Charger | Auto PWRJUMP (quick-charge capability) |
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Cordless 4-1/2 inch angle grinder with a digital brushless motor. Designed for grinding and cutting a variety of materials. Includes a 5.0 Ah PWRCORE 20 lithium battery, a PWRASSIST USB adapter, and an Auto PWRJUMP charger. The tool has a dual-function lock switch with lock-on capability, a soft-start feature, tool-less guard adjustment, removable dust screens, and onboard wrench storage.
Model Number: AG2907-1A
Skil PWR CORE 20™ Brushless 20V 4-1/2 IN. Angle Grinder Kit Review
What stood out in use
I put the Skil 20V grinder to work on a mix of chores—cutting 3/8-inch rebar, trimming rusty bolts, shaping angle iron, and surfacing welds on mild steel. It’s a compact, brushless 4-1/2-inch grinder with a single 8,500 RPM gear ratio, and it behaves like it. Power feels confident and consistent for its class, without surging or laboring when you lean in. The soft-start is immediately noticeable; the wheel spins up smoothly without that jump-in-the-hand that some grinders have. Once it’s up to speed, it’s a familiar, no-nonsense grinder experience: fast material removal, predictable spark pattern, and enough torque to keep the disc from bogging in typical homeowner and light-pro cuts.
The kit includes a 5.0Ah PWRCORE 20 battery, Skil’s Auto PWRJUMP charger, and a PWRASSIST USB adapter. That combination makes this a genuinely complete package—you can get to work right away and keep a phone or laser topped off on site without carrying an extra power bank.
Setup and features that matter
- Brushless motor: It’s quiet for a grinder and runs cool. I noticed less housing heat during extended grinding than with older brushed units.
- Dual-function lock switch: It’s a slide switch with a safety detent, then a further push to lock on. The soft-start ties into this nicely.
- Tool-less guard: The guard rotates with a spring lever and locks positively. It didn’t drift, even when nudged against stock.
- Onboard wrench storage: The pin spanner hides in the handle cap. I never had to fish through the toolbox for it.
- Removable dust screens: These pop off and clean easily. After cutting pavers and mortar-struck brick, I rinsed them and knocked out fines with compressed air.
- PWRASSIST USB adapter: It snaps onto the battery and provides USB power. I used it to charge a phone and a headlamp between tasks.
- Auto PWRJUMP charger: It brings a depleted pack up to usable levels quickly. A few minutes on the charger was enough to finish a cut I’d started.
The side handle threads in multiple orientations, including a top position, which I like for tight cuts and vertical grinding. The die-cast gear case is compact, and the overall length (about 12 inches) makes it easy to get into tighter spots compared to bulkier 5-inch models.
Ergonomics and control
The balance with the 5.0Ah pack is back-heavy in a good way. It takes weight out of the nose and makes one-handed maneuvering safer when you’re positioning the guard or lining up a cut. Grip diameter is comfortable with gloves, and the rubber overmold does a decent job of damping vibration. The switch itself is on the stiffer side: wearing gloves, I had to be deliberate about sliding it past the safety detent, and initially I overshot the lock-on a couple of times. After a few sessions, muscle memory kicked in and it stopped being a thought.
The guard lever is reachable and easy to operate with gloves, and the detents are strong. I like the top handle position for scoring and for flanged grinding where you want your wrist straight; Skil’s head design makes that grip feel natural.
There’s no electronic brake here, so the wheel coasts down for a couple of seconds after shutoff. That’s normal at this price point, but worth remembering when you set the tool down or reposition in a tight area.
Cutting and grinding performance
On 1/8-inch steel plate with a 36-grit flap disc, material removal was steady and controllable. With a 0.045-inch cutoff wheel, I could rip clean slots without stalling if I let the wheel do the work. Cross-cutting 3/8-inch rebar, the grinder maintained speed through the cut; slowing it down by force just glazed the disc rather than choking the motor, which is what I want to feel from a brushless setup with decent electronics.
Heat management is good. After a run of five or six long cuts, the head was hot (as any grinder will be), but the motor housing and battery weren’t cooking. The dust screens clearly help—after a few masonry passes, the screens captured a surprising amount of grit that would otherwise migrate into the windings.
Vibration is average for a 4-1/2-inch grinder—no odd rattles or resonance. Noise is typical grinder loud; you’ll want hearing protection.
Runtime and charging
With the included 5.0Ah battery, I was able to alternate between grinding and cutting for a couple of sessions before needing a charge. In continuous heavy grinding, you’ll burn through the pack in short order—any cordless grinder will—but for mixed work it’s more than serviceable. The big win is the Auto PWRJUMP charger: a quick pit stop puts enough juice back in the pack to finish what you were doing. In practice, I’d do a batch of cuts, pop the battery on the charger while I measured or deburred parts, and get right back to it. Full charges take roughly an hour with the 5.0Ah pack in my experience.
If you plan to do extended grinding (weld prep on a trailer, for instance), a second battery is the real unlock. With two 5.0Ah packs and the quick-charge behavior, you can work continuously at a moderate pace.
Dust and maintenance
I appreciate the removable screens. Brick dust and grinding swarf are brutal on motors, and being able to rinse and blast out those screens extends life and keeps the tool running cooler. The guard mechanism didn’t jam up after masonry work, and the spanner’s home in the handle cap meant wheel changes stayed efficient. Keep an eye on the arbor flange; a drop of machine oil now and then keeps it from seizing if you switch between thick and thin wheels frequently.
What you don’t get
- Variable speed: It’s a single-speed grinder. If you do a lot of stainless finishing, stone polishing, or wire-brushing where lower RPM helps, you’ll miss speed control.
- Electronic brake: The wheel coasts down. Not a deal-breaker, but it’s a feature some higher-end grinders include.
- Advanced kickback control: There’s no electronic clutch. Respect the bind; use the guard and your handle.
Those omissions are common at this tier, but they define who the tool is for.
Durability and build
Nothing in my testing raised concerns. The head casting is tidy, the guard is stout, and the battery latches feel secure. I tossed it in and out of a truck bed and shop floor routinely. The switch never clogged even after masonry dust, and the motor tone stayed smooth. Long-term battery health will always depend on storage and charging habits; I didn’t see excessive heat buildup or odd pack behavior, and the USB adapter didn’t wiggle or loosen under use.
Value and who it’s for
As a kit, this is strong value: you get the grinder, a high-capacity 5.0Ah battery, a rapid charger, and a USB adapter that’s actually useful on site. Performance is squarely in the “confident DIY and light pro” zone. If you’re fabricating all day or cutting thick stock constantly, a high-output grinder on a premium platform or a corded 11- to 13-amp unit will still win on sustained power. But for jobsite punch-list work, automotive repair, fence and gate fabrication, masonry touch-ups, and general shop tasks, this Skil hits a sweet spot of power, runtime, and convenience.
Recommendation
I recommend the Skil 20V grinder for users who want a capable, cordless 4-1/2-inch grinder with thoughtful touches and a genuinely useful charging ecosystem. It cuts and grinds with authority for its class, the soft-start and tool-less guard improve safety and workflow, and the included 5.0Ah battery plus quick charger minimize downtime. You give up variable speed, an electronic brake, and advanced kickback control, but if your work doesn’t demand those features, this kit is a practical, well-rounded choice that’s easy to live with on a daily basis.
Project Ideas
Business
Mobile Metal Cut & Grind Service
Offer on-site cutting and grinding for gates, railings, fence posts, and rusted bolt removal. The cordless 20V setup and quick-charge let you work in tight or power-limited areas. Package pricing: per-cut fees for rebar/bolts, hourly for fabrication prep; upsell surface prep for paint.
Concrete Edge Finishing for Countertops & Pavers
Specialize in beveling, rounding, and polishing concrete edges for DIYers and small contractors. Provide per-linear-foot pricing with tiered finishes (grind-only, satin, polish). Use tool-less guard adjustment to switch from cutting to finishing quickly; bring a water bottle and shroud for dust control.
Tile Trimming and Problem-Cut Concierge
A mobile service for homeowners needing tricky cuts: U-cuts around outlets, L-cuts, and scribe fits. Charge a service call plus per-cut rate. Cordless operation simplifies on-site work; the brushless motor ensures smooth cuts on porcelain with a diamond blade. Offer add-ons like edge chamfering.
Artisanal Metal Decor Micro-Brand
Batch-produce small garden stakes, wall hangings, and minimalist shelves from flat bar and sheet offcuts. Use the grinder to cut profiles, clean welds, and add brushed finishes. Sell on Etsy/markets; differentiate with limited runs and custom initials. The USB adapter keeps your phone and POS device powered.
Property Maintenance Bolt & Rebar On-Call
Partner with remodelers and HOAs to provide rapid-response cutting of seized fasteners, protruding rebar, and angle-iron. Offer monthly retainers with priority response. The lock-on switch aids longer grind-downs; removable dust screens maintain performance in dusty environments.
Creative
Reclaimed Metal Garden Sculptures
Turn scrap steel, rebar, and old tools into welded garden art. Use the 4-1/2 in. grinder to cut elements to shape and smooth welds flush. The soft-start and lock-on switch aid in long, controlled grinds, while the brushless motor and 5.0 Ah battery give you steady power for shaping, beveling, and polishing details.
Live-Edge Steel and Wood Side Tables
Cut and square steel tubing for legs, notch angle-iron brackets, and grind welds clean for a modern-industrial table. Tool-less guard adjustment lets you quickly switch angles between cutting and grinding, and removable dust screens help keep airflow clear when moving between wood and metal work.
Concrete Terrazzo Coasters and Planters
Cast small terrazzo pieces, then use a diamond blade to trim edges and the grinder to round and polish rims. The 8500 rpm speed gives clean cuts on cured concrete; lock-on helps maintain consistent pressure during edge finishing. Quick-charge keeps you moving between batches.
Mosaic Tile Wall Art and Inlays
Shape porcelain/ceramic tiles into custom curves, inlays, and geometric patterns. The cordless design makes outdoor cutting easy (less mess), and the tool-less guard lets you pivot quickly for bevels and reveals. Use the PWRASSIST USB adapter to power a small LED task light for detail work.
Upcycled Bike Chain and Gear Clocks
Cut and deburr bike chains, grind down sprocket edges, and polish faces for sleek wall clocks. The compact 4.14 lb body gives good control for intricate deburring, and the soft-start reduces chatter when touching delicate parts.