SanDisk 400GB Ultra MicroSDXC UHS-I Memory Card with Adapter - 100MB/s, C10, U1, Full HD, A1, Micro SD Card - SDSQUAR-400G-GN6MA

Bought this for my Paralenz underwater camera that shoots up to 4K 30fps. My camera manufacturer says 128gb V30 is the required max but this card is rated for a min of 10mb/sec & and the write speed is undocumented publicly after contacting Sandisk, with transfer speeds to 100mb/sec. Maybe they won't release write speeds because it performs so well they don't want it competing with their faster rated cards?.... just speculation of course! But this card performs flawless... not only in my Galaxy Note 4 phone but also in my camera. Leave it formatted in the default exFat and your good! After much research it appears its only weakness may be in burst abilities for use as internal memory but sustained transfer rates are great!... so much so that 4k @ 30fps video was no problem in testing. I'm also astonished this card works so well in my Note 4, I had a 128gb Sandisk in before and this definitely feels faster. At this point I have the highest recommendations for this card.... you can now store mass amounts of 4K footage.... according to my tests so far, about 10+ Hrs of 4K @ 30 fps! I've found other brands often give similar speeds as compared to Sandisk but fail miserably long term in reliability.... Do you really want 400 GB worth of stuff lost because you wanted to save a few bucks with another brand? Sandisk is the most reliable IMO and it's amazing they remain at the front of the pack. It's not the fastest dog out of the gate that wins, but the one who can make it to the finish line first! I own 3 of these now. I can film 2.7k @ 60fps and put 17 one hour dives in a week long dive vacation and I only use about 180gig! Its great not having to tote a big laptop on my trips! I have one just for backup too on my trips .. Haven't had to use it yet!

Summary: the SanDisk Ultra 400GB seamlessly adds what amounts to unlimited storage for your phone. I've had it installed and working well on a Samsung Note 9 for the last three months. After putting the SanDisk Ultra 400GB in place on my Samsung Note 9 , I don't think I'll ever run out of space on my phone. I love this: I never really have to download pictures or video from my phone, and I can permanently store whatever movies, documents, or other files I wish. Even after shooting thousands of photos and hours of video, I have hundreds of gigabytes of free space left. On the Samsung Note 9, the 400GB card reports 366.8 GB of free space after formatting. Using a speed testing application, my card reports write speeds of 48 MB/s and read speeds of 86 MB/s. Suggestions: * After purchase, get an SD card speed testing application to verify that your card isn't fake, and that its performance approaches SanDisk's hyped theoretical maximum. Don't be put off if you don't reach 100 MB/s or whatever the advertised maximum speed might be; you just want to be somewhere in the ballpark. If you are using Android, you can download an excellent SD cart-testing application from the Play store called "SD Card Test." * On some Android devices you can further verify that you have a legitimate (not fake) card by downloading an application called SD Insight (note this app is not compatible with the Galaxy Note 9 and some other late-model Android devices.) note: I was *not* solicited to write this review, and I bought this product with my own money. I received no compensation for this review and indeed I have no idea who the seller might be. I pride myself on writing unbiased reviews.

I love it! Works great in my Galaxy Note 8! Fast enough that I can throw pretty much anything at it. If you're wondering, modern Android versions (starting with Lollipop, as I recall) have the ability to read up to 1 TB of external storage. While this 400GB card is the maximum capacity you can currently buy*, the leading manufacturers are feverishly working to make larger capacity cards. For now, though, I think 400GB is enough to handle all the 4K video I can shoot. *- Don't be fooled by unscrupulous sellers, particularly on auction sites ( I won't name it because there are a lot of fake cards here, too), who list ridiculously large capacity cards for astonishingly low prices... you don't get what you pay for! They take cheap, generic cards, usually no more than 4 or 8 GB, and rewrite the card's firmware & re-label it to make it act and appear like a larger card... 256GB, 500GB or higher! There are tons of listings out there for 1 TERABYTE microSD cards! Of course there's no such thing: and when the physical memory of the card is reached, your device will simply start overwriting data... and your precious photos, videos and other files will be gone forever. In fact, one third of all SanDisk cards on the market are counterfeit! You can avoid all this by installing and using a free app called SD Insight to determine if your card is legitimate.

I bought two of these on sale about 2.5 years ago. One of them went in my phone, where I used a lot of storage for multimedia I would watch on long trips. Recently the card died on me with little notice. My phone listed it as "corrupted" then stopped recognizing it. It could not be formatted, erased, or written to. Apparently this happens when it reaches the end of its life cycle, which seemed a little soon to me. Fortunately the card fails safe, so I was able to access it on my computer with a reader and copy all the data on it. Typically, I wouldn't consider a storage device like this to be very good if it dies after 2 years. Again, this wasn't damage to the card, but the end of its life cycle. But checking my purchase history on Amazon I discoveredit came with a 10 year limited warranty. I contacted customer support and discovered the warranty covers this. A replacement card is being shipped. Total time is going to be about a week to a week and a half, which I consider very reasonable. While it's unfortunate I had a serious problem with one of my cards, I always appreciate good customer service and a company that stands behind its products and honors their warranties. I believe anyone could buy this product with confidence. My other, less used card, is still functioning fine.

Not much to say other than to remark on the validity of the SD card I received through Amazon actually being from SanDisk. SanDisk is one of, if not the biggest, SD card manufacturer and the quality of their products is the golden standard. So capacity, performance, and reliability goes without saying for these SD cards. However, I have read quite a lot of reviews claiming that the ones they received were imposters and, while I do not claim they are mistaken or not, I can say that my 400GB one I received from Amazon seems to check out through every test I've run it through. Amazon has quality customer care and product replacement/return policies for the ginormous corporation they are, so if you have any issues with your product I'm sure you can get it worked out within reason. There are a lot of different resources for checking the validity of SD cards online and you can find them all with a simple search on a quality search engine website. If you are concerned, I suggest going that route or contacting local IT support to see what they can do for you. PROS: SanDisk. Enough said. Quality and performance. CONS: Obviously, verrry slim chance of the SD card being a fake. Technology is amazing these days and there are people out there driven to make a quick buck if they've got the materials and the know-how. Even giants like Amazon can fall victim to these numerous and unethical kinds of practices. Happy with my purchase. 100% 400GB SanDisk SD card at a reasonable price.

I picked up the 400 GB version during Prime Deals for my Switch. Knowing that Nintendo is a little weird about storage formats, I searched its website to see what Nintendo recommended when replacing SD cards for the Switch. As it turns out, Nintendo very sternly recommends fully formatting SD cards with a special tool before using them in a Switch. "Nintendo recommends using the SD Association's SD Memory Card Formatter to format any SD cards that will be used with a Nintendo product. Nintendo products strictly adhere to the SD card standard. Instructions on using this tool can be found at the bottom of the tool's page on the SD Association website. Please select Overwrite format when formatting the card." The SD Association's site provides "It is strongly recommended to use the SD Memory Card Formatter to format SD/SDHC/SDXC Cards rather than using formatting tools provided with individual operating systems. In general, formatting tools provided with operating systems can format various storage media including SD/SDHC/SDXC Cards, but it may not be optimized for SD/SDHC/SDXC Cards and it may result in lower performance. SD/SDHC/SDXC Cards have a ‘Protected Area’ for SD Card security purposes. The SD Memory Card Formatter does not format the protected area in the SD/SDHC/SDXC Cards. The protected area shall be formatted by an appropriate PC application or SD host devices that provide SD security function.” In other words, unless you format your SD card with the tool from the SD Association's site, the secure sectors of the card get lumped in with the rest of the storage, slowing down the card. A quick format in Windows won't cut it here. I'm willing to bet this has caused the vast majority of one-star reviews complaining of poor SD card performance on Switch. I followed Nintendo's directions for formatting and the card performs perfectly. It seems a bit faster than my old card. A nagging data corruption issue I had with my BoTW install has stopped completely.

Notice: Review is subject to change if problems occur down the road. Never had an issue with Sandisk before, though. I checked online for images to compare, my 400GB card and packaging look legitimate. Buy from Amazon directly if there's a concern about hardware piracy. This 400GB model had Amazon Services Inc as the seller and was eligible for Prime so I'm certain it's authentic. I'm not alone in reporting that the FORMATTED capacity of the card is 366GB. These disks do tend to sell advertising the unformatted capacity. Took me a while to get the card into the caddy on my Note9, but booting up the phone after installing, I had no problems accessing data I'd copied to it earlier - 1800 camera photos appear rather fast. I didn't run any professional benchmark tests but it's faster than the 256GB card I was using before when loading. Wow. Reading others' reviews, heating may be an issue. I only use the card for backup purposes but will keep an eye on it. Frequent/heavy use might be a concern, and given the tiny size of these cards, heating would become an issue. For $160, seems a good deal. Better than $260 for the same card elsewhere or even $360 for the 512GB version -- but there are times for the extra capacity that necessitate the cost. 400GB (or, rather, 366 formatted) is rather nice, especially for the snappier speed.

What can be said it's the biggest storage to date if you need the biggest you can use. I had the 200GB card installed in my Switch but even that couldn't hold everything I needed. Why, the DLC and updates and Games downloads will eat up your capacity if you buy alot of Switch Games and then Digital. It does cost to go 400GB but the payoff is I now have another 200GB+ after transferring all the data over to the 400GB card. Before I was running extremely low under 80GB-once I started to filling the 200GB card. As for speed I don't see what others are talking about and have no load and run issues from the 400GB. Might be different because it is a NS but it doesn't show any game load lags or performance issues for me. As to the Digital loading I don't see any problems loading. So with MicroSD cards everyone's load or performance could be attributed to hardware compatibility issues rather just the MicroSD is the cause. If your hardware is of older Generations then a newer card wouldn't perform well just for the reason of hardware itself most likely wasn't made for the newer cards. My recommendations to NS owners yes it does cost more to go 400GB but you will thanks yourself for the capacity and yes the 400GB will drop in prices if any only if when the 1TB MicroSD comes out and that isn't anytime soon. Update: if Switch users aren't following the instructions on Nintendo site on microsd card upgrade and migration then any failures from user fault not following instructions isn't Amazon or Nintendo fault.

エラーもなくカメラ写真やダウンロードした映画や動画、音楽ファイルの保存に役立っています。 まだ使い始めですが、今の所大満足です。

I received this memory card today. I am really impressed with the performance. I am using memory card with my surface pro tab. Before i bought this i have used Samsung UHS-3 memory card though it is Class 10 it is almost competing with UHS-3 memory card. Reading speed is as promised, It is about 100 MB/s.(I have SSD in my laptop so writing onto destination is supported). Writing speed is not disclosed by Sandisk but in my test it really impressed me. IYou can write upto 45 MB/s. I tried copying from internal SSD to memory card(Single 2GB file) wrting speed was around 46 MB/s. I tried with copying from USB 3.0 HDD(Seagate) writing speed was 41 MB/s. I have used UHS-3 memory card reading speed is mostly similar with this but writing speed is better than this. But considering the price it's worth it.

同じSandisk Ultra Microsdxcの２００GBのマイクロｓｄカードもありますがスマホ装着時の書き込みは圧倒的に遅いです．

Tested the complete card with H2testw tool, 100% passed after some hours. Using it both in my Nintendo switch and switch lite with no issues!

what a bargain got 400gb with a price of 128gb