Comparison Panasonic ES-RT77 vs Panasonic ES-GA21

— Built-in trimmer. Device for trimming the contours of facial hair. A trimmer is similar to a clipper, but smaller and better suited for fine work. Located directly on the body of the device.

— Blade for hair cutting. Removable version of the trimmer (read more about the trimmer above), made in the form of a replaceable nozzle and is installed instead of the main nozzle with shaving heads. Thanks to this, the trimmer can be made wider than the built-in trimmer, and overall more efficient.

— Nozzle for ears and nose. The cylindrical nozzle of small diameter allows you to penetrate the inlet and ear and remove unwanted vegetation from there. It is installed mainly on top of the main nozzle.

— Universal comb. Such a nozzle can be useful for regular care of the stubble or beard, when you need to trim, shorten, and not just shave. Length adjustment allows you to select the desired value for a particular area or depending on the image and type of "hairstyle".

The speed of rotation of the electric motor of the shaver. A higher rotational speed (ceteris paribus) usually means a higher speed of movement of the blades, which has a positive effect on the closeness of the shave.

Model of replacement head(s) compatible with electric shaver. This data will be useful primarily when looking for spare nozzles.

— Turbo mode. The function of a short-term increase in the speed of rotation of the motor. This increases the performance of the shaver, which can be especially important when working with thick hair or in hard-to-reach areas. Note that the turbo mode, usually, is not intended for long-term operation.

— Auto-detection of bristles. The electric shaver's head contains a sensor to detect bristle density or stiffness. Through the automatic stubble feature, the shaver's motor adjusts power according to the skin area's requirements. This capability facilitates effective one-pass shaving, even with thick stubble. As the shaving head transitions from dense to moderate bristles, the motor power decreases automatically. This not only conserves battery life but also provides a gentler experience for the skin.

— Floating head/foil. The floating or movable shaving head(s) are capable of moving relative to the shaving unit and shaver body. Such a system follows the contours of the face during shaving, which ensures a tighter fit of the shaving heads to the skin, as a result — a cleaner and better shave, especially in difficult areas.

— Possibility of washing with water. Possibility of washing the shaving unit with water. This method is often much more convenient and effective than dry cleaning with a brush or other method.... Note that being washable with water does not necessarily mean wet shaving (see above).

— Cleaning indicator. A special indicator that notifies the user of the need to clean the shaver.

— Self-sharpening blades. Blades made using a special technology, thanks to which they sharpen themselves, due to friction against each other in the process. Thus, the blades remain sharp at all times, and their maintenance is limited to the replacement of worn blades.

— Child lock. Shavers featuring a safety switch are designed to activate only when held in the user's hand and intentionally turned on. This design prevents unintended activations, such as during travel when the device might shake inside luggage, avoiding unnecessary battery drain during idle moments.

— Additional Blade. A replacement cutting module that is installed instead of a dull one to restore a clean cut without irritation and maintain the device's trademark "versatility." Having a spare allows for flexible maintenance planning — you won't depend on the availability of consumables in the store, can keep a separate blade for contours/edging or travel, and maintain hygiene by dividing the application area. The practical effect — fewer pauses, consistent results every week, and predictable expenses, making this configuration more advantageous and convenient compared to options "with only one blade."

— Case. Cases include all sorts of hard constructions for storing the razor. This category also includes pouch-type cases made of dense fabric. Besides securely storing the device, they also elevate the model to a higher class. More budget-friendly electric razors come with a much more primitive fabric case.

— Charging Stand. A special stand on which the razor can be placed to charge the batteries. There are no fundamental technical differences between such charging and charging via a network cable; the main difference is that the stand can also be used for storing the razor. Therefore, razors with a charging stand are well-suited for home use.

— Wireless Charging. A special stand that charges the razor witho...ut a precise plug connection — simply placing the electric razor on it will automatically begin charging the battery unit. This spares the user from fiddling with connecting wires and reduces wear on connectors. On the other hand, such a feature significantly impacts the cost of the razor and increases the duration of the charging process itself, as the charging platforms are made low-power for safety reasons.

— Self-Cleaning Station. This is a special stand where the razor is installed for automated maintenance. As the name suggests, this maintenance primarily includes cleaning — the shaving block is cleared of hairs and dust — as well as recharging the battery. Additionally, self-cleaning systems may include lubrication and disinfection of the shaving block, though this feature is somewhat rarer and requires the use of consumables (oil and disinfectant).

The average runtime of electric shavers on a full battery charge, without recharging, is generally overestimated due to factors like hair length, density, and trimmer usage. Manufacturer claims for runtime tend to be higher than actual usage. Longer runtimes require heavier and more expensive powerful batteries. Most shavers offer around 45 minutes of runtime, while some models provide up to 1 hour or as low as 30 minutes of operation.

The presence in the design of the electric shaver charge level indicator.

It's important to highlight that in this context, an indicator refers specifically to a visual representation of the charge level. This could manifest as a battery icon or a percentage displayed on the display. Such an indicator significantly simplifies battery monitoring, minimizing the possibility of being unexpectedly left with a depleted battery.