In getting ready for my next family vacation, I felt the need to obtain some additional batteries for my DJI Osmo Action 4. I found the Palowextra 2 Pack OSMO Action 4/3 Battery Replacement with Charger Kit and decided to spring for this set given that, amongst the other like products I found, this seemed the most similar in size and form factor to my OEM battery charger and was offered at a decent price.The Palowextra 2 Pack OSMO Action 4/3 Battery Replacement with Charger Kit came with the battery charger, two batteries, a micro/standard SD card reader, and the instructions. The charger is a little smaller than the DJI Osmo Action 3 Multifunctional Battery Case (Model AC2CH). It measures approximately 4.35” long by 2.33” wide by .89” deep (OEM measures 4.56” long by 2.32” wide by .9” deep). The case is similar to the OEM case however the Palowextra case has battery level indicator lights, clearly showing 100%, 75%, 50% and 25% battery charge level where the OEM case only has a single light for each battery that changes color depending on charge level. You can check the battery level by pressing the button in the middle of the two micro SD card slots which will illuminate the LED battery display. The battery case supports USB, with a built-in USB cable, as well as USB-C (cable not included). Consistent with the OEM case, the Palowextra case has storage for two micro SD cards.Batteries with this two-pack of Osmo Action 4/3 replacement kit are the same size as OEM but do differ in specs. Specs listed on the Palowextra batteries indicate the rated capacity at 1800 mAh (OEM lists 1770 mAh) and the rated energy at 6.93 Wh (OEM lists 6.81 Wh). Both the OEM and these replacement batteries are manufactured in China.When charging, I found that these batteries charged from about 50 - 75% (as shipped/received) to full in approximately one hour utilizing a 5V USB brick (recommended by the included instructions) and the attached USB cable. The Palowextra set does not include a charging brick. Unfortunately, the built-in USB cable falls short at only about 8.5” — which may prove too short to reach any standard US electrical outlet while sitting on a flat surface like a countertop or floor. I also found that when the battery level is below 25% (13% in my case), the indicator still indicates a 25% charge as there are only four lights corresponding to battery level with 25% being the lowest. In my opinion, an indicator light at 10% would’ve been a bit better. As I have not utilized the USB-C charging port yet, I cannot attest to the time it would take to charge batteries using a USB-C cable.During use, I was able to get almost an hour out of one battery at 4K 120/RS. The rear screen was active for approximately ten minutes of the fifty-three. Battery drain seemed even throughout and my Osmo Action 4 finally overheated after fifty-three minutes with the battery at 13%. This may have been a result of the rear screen being on a portion of the time but could have also been from the off-brand battery use (I am unable to confirm which but have never had issues with overheating using the OEM batteries previously). As mentioned, although a charge level of 13% was showing on my Osmo Action 4, the Palowextra charging case reflected a 25% charge when the battery was reinserted into the case. My Osmo Action 4 was warm to the touch but the Palowextra battery was not as warm. For testing purposes, my Osmo Action 4 remained stationary on a table in optimal indoor conditions.Overall, I’m happy with the Palowextra 2 Pack OSMO Action 4/3 Battery Replacement with Charger Kit. While it lacks some of the features of the OEM Multifunctional Battery Case (stores only two batteries instead of three, doesn’t seem to have fast charging capabilities, and cannot be used as a power bank), there are some features of the kit that I do like and the batteries seem to work well for my needs. Only time will tell if these batteries will hold up like the OEM batteries with frequent use and in different, somewhat harsh conditions.