The Panasonic ER-SB40 is a high-performance beard trimmer designed for short to medium-length beards, featuring a powerful 9,800 CPM linear motor and 19 adjustable length settings. GQ praised its precision and consistency but noted the bulky design makes it less ideal for detailed work around the jawline. While it offers cordless operation with up to an hour of use and a waterproof build, reviewers found the weight and battery life limiting for extended use. It's best suited for users who prefer shorter beards and want a reliable, durable trimmer for regular maintenance.
Full review
Performance and Motor Power
Panasonic's ER-SB40-K stands out with its 9,800 cuts per minute linear motor, a claim the company asserts as the fastest for consumer trimmers as of August 2017. GQ's Owen Gough noted that this high-speed motor delivers 'a decimation of unwanted beard hairs in reasonably short order and surprisingly few nicks and pulls.' The motor's consistent performance across varying hair densities was particularly praised, maintaining a constant speed that results in 'smooth, even results and a smoother trim.' However, the motor's power does come with trade-offs; the trimmer's heft and the need for substantial energy input make it less ideal for extended cordless use.
Blade Quality and Hair Handling
The Panasonic ER-SB40-K features ultra-sharp, wide-tipped blades made from hypoallergenic stainless steel, designed to lift and cut through even the most unruly hair. According to the product documentation, these blades are engineered to capture more hair in one pass, reducing the need for multiple passes and minimizing tugging. GQ reviewer Owen Gough emphasized that the blades are 'hypoallergenic, razor-sharp' and keep irritation and skin burn to a minimum. The wide blade design allows for vertical trimming to create sharp beard lines, which is a feature particularly appreciated by users aiming for precision styling. However, the same reviewer noted that the blade's effectiveness diminishes with longer hair, where the risk of accidental cuts increases. The blade's rounded tip is specifically designed to enable clean, sharp lines when used vertically against the skin, which is a unique advantage for detailed beard shaping.
Adjustability and Length Settings
The trimmer offers 19 adjustable length settings ranging from 0.5mm to 10mm, controlled by a quick-adjust dial positioned on the handle. This dial allows for precise adjustments in 0.5mm increments, providing users with a wide range of options for maintaining different beard styles. GQ's Owen Gough appreciated the ability to 'switch up on the fly for experimentation mid-shave' and noted that the haptic dial wheel made the process 'low-effort grooming.' The comb attachment is essential for achieving these precise settings, though trimming without the attachment results in a trim of approximately 0.5mm. RTINGS confirmed that the dial's responsiveness is excellent, enabling quick transitions between settings during use. However, the trimmer's focus on shorter beard styles becomes apparent when users attempt to work with longer hair, where the 10mm maximum setting may not be sufficient for maintaining a neat appearance on longer facial hair.
Battery Life and Cordless Functionality
Panasonic advertises up to 60 minutes of cordless operation, which aligns with RTINGS' findings that the device can handle a full hour of trimming before requiring a recharge. The trimmer's battery is fully charged in one hour, and a five-minute charge provides enough power for a couple of minutes of trimming. However, GQ's Owen Gough criticized the LED battery indicator, which only shows 'full,' 'mid,' or 'low' — a vague display that he found unhelpful when rushing to get ready for work. The cordless functionality is particularly useful for users who want to trim in the shower, as the device is waterproof and can be used cordlessly when unplugged from an AC outlet. This feature adds convenience for users who prefer to groom in the shower, though the device's weight and size may make it less portable than some competitors.
Design and Build Quality
The Panasonic ER-SB40-K is a substantial device, described by GQ's Owen Gough as a 'huge gadget to hold in your hand, store in your cabinet, and take with you on your travels.' The rubberized grip and ergonomic design provide better control during trimming, though the device's heft can make it challenging to maneuver around the jawline. The crosshatched grooves on the sides and back prevent slippage, and the flat bottom allows it to stand upright on countertops. The device also comes with a travel pouch and a travel lock, which are useful for travelers. However, the size and weight of the trimmer make it less suitable for frequent travelers, as it adds noticeable weight to an overnight bag, according to RTINGS.
What Reviewers Loved
Reviewers consistently praised the Panasonic ER-SB40-K's powerful motor and ability to handle thick, dense hair with minimal tugging. GQ's Owen Gough highlighted the trimmer's 'supremely capable tool perfect for short beards and stubble' and noted that the 'hypoallergenic, razor-sharp blades keep irritation and skin burn to a minimum.' The 19 adjustable length settings were also a major selling point, with RTINGS noting that the quick-adjust dial allows for 'precise adjustments in 0.5mm increments' and 'low-effort grooming.' The waterproof design was another feature that received positive feedback, as it allows for cordless trimming in the shower, which is a significant advantage for users who prefer to groom in the shower. Additionally, the device's ability to be used both corded and cordless, with a full hour of battery life, was appreciated for its versatility.
Where It Falls Short
Despite its strengths, the Panasonic ER-SB40-K has several drawbacks that limit its appeal. GQ's Owen Gough criticized the device's size and weight, noting that it 'can be a little unwieldy to maneuver around your jawline' and that 'the initial testing required some nimble wrist work to ensure I didn't slice through the longer hairs on my chin accidentally.' The device's heft makes it less suitable for frequent travelers, as it adds noticeable weight to an overnight bag. Additionally, the battery indicator's vague display, showing only 'full,' 'mid,' or 'low,' was a point of frustration for GQ's reviewer. The trimmer's focus on shorter beard styles is another limitation, as the maximum 10mm setting may not be sufficient for users who want to maintain longer beards.
Who It's Best For
The Panasonic ER-SB40-K is best suited for users who primarily maintain short to medium-length beards and require a powerful trimmer to handle thick, dense hair. GQ's Owen Gough emphasized that it's 'a mighty addition to any bathroom, both in capabilities and physical size,' making it ideal for those who prefer a robust, high-performance tool. The device is particularly well-suited for users who want to trim in the shower, thanks to its waterproof design and cordless functionality. However, it's not ideal for frequent travelers due to its size and weight, and users seeking a more versatile trimmer for longer beards may find the 10mm maximum setting limiting. Users who value precision and consistency in their grooming routine will find the 19 adjustable length settings and the quick-adjust dial particularly appealing.
Strengths
- +High-performance linear motor delivers 9,800 cuts per minute for efficient trimming of thick, dense hair
- +19 precision length settings (0.5MM to 10MM) with quick-adjust dial for customizable styling
- +Ergonomic rubberized grip provides better control during use
- +Waterproof design allows for cordless trimming in the shower and easy cleaning
Watch-outs
- −Large, heavy design makes it unwieldy for precise jawline trimming
- −Battery life lasts only 60 minutes, which may be insufficient for longer grooming sessions
How it compares
The Panasonic ER-SB40 has a powerful motor and waterproof design, which the Norelco 3000 Series lacks. However, it's bulkier and has shorter battery life than the Wahl Groomsman. It's ideal for those who want a durable, waterproof trimmer but may not suit those needing extended runtime.
Who this is for
At a glance: users wanting durable, waterproof trimmer.
Why you’d buy the Panasonic Beard Trimmer for Men Cordless Precision Power Hair Clipper with Comb
- High-performance linear motor delivers 9,800 cuts per minute for efficient trimming of thick, dense hair.
- 19 precision length settings (0.5MM to 10MM) with quick-adjust dial for customizable styling.
- Ergonomic rubberized grip provides better control during use.
Why you’d skip it
- Large, heavy design makes it unwieldy for precise jawline trimming.
- Battery life lasts only 60 minutes, which may be insufficient for longer grooming sessions.
Rating sources
“For tidying up shorter beards, Panasonic's super-charged ER-SB40 is best in class.”
“this isn't very specifically a shaving razor but that was what I bought it for I know that there's some really high-tech ones but sometimes you don't need to go high-tech to get what you want”
“If you're rocking anything from heavy stubble up to a full lumberjack beard, the Panasonic ERGB86 is built to handle it.”
Our 3.5 score is the average of these published ratings. Ratings marked * were derived from the reviewer’s written analysis or video transcript — the publisher didn’t print an explicit numeric score, so we inferred one from their own words. Click through to verify. More about methodology.
