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

This was just what I needed to use with my digital camera. No problems. I appreciate its good quality, ample storage space, and value for money.

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!

Purchased 2 of these for our cell phones. ScanDisk has always worked great.

For dashcams and other continuous loop recordings: Sandisk markets a "high endurance" 256gb card @ $52, but it is a terrible deal compared to this 400gb SanDisk Ultra. The main selling point of a high endurance card is1) it can take additional writes. This card can too since it also has storage space above 256gb, except unlike the 256gb card you can access the additional storage space from the get go, which is hugely important to increase the look-back period of your dashcam. 256gb is the current max storage for high endurance cards, if you want more storage you either have to periodically back up data to a hard drive or... you could just get the 400gb Ultra.2) Some durability features. SD cards have zero moving parts, any condition that would destroy the Ultra would likely destroy the equipment containing it. There is only a narrow survivability delta, if any, where the high endurance would survive conditions that the ultra doesn't.3) Warranty. The high endurance only offers 2 years warranty compared to 10 years on the ultra, but in the warranty terms the Ultra does not cover failures due to use in applications like dash cams. This is BS as all SD cards are already warranty-limited by write cycles. Write cycles are write cycles, regardless of whether they occur in a dash cam or a normal camera. Nevertheless this warranty is unnecessary as a) failures of legit microsds are extremely rare even in "high endurance" scenarios, and b) the costs of cashing in the warranty likely exceed the value of the replacementIn terms of compatibility, many pieces of equipment will claim to have a limit of say 128gb but take this card just fine.In terms of write speed, a peak of 100MegaBytes/s is plenty for most consumer grade cameras. I've used it in an action camera and it can take sustained 4K 170 Megabits/s video (170 megabits = 20 MegaBytes) no problem.TLDR/Bottom line: If you can afford it and if you plan on using the card in a scenario where you might possibly, at some point need maximum storage, this is the option that provides the best value.

This card has not disappointed me yet. With huge amounts of space, and a transfer read speed listed at 100MB/s, it's a card that can serve all kinds of purposes—assuming your device supports this storage amount—for photos, music, videos, and just plain old file storage. I am using mine with the new Sony NW-A45/L Walkman with Hi-Res Audio, Moonlit Blue (2018 Model), and it has worked marvelously so far, with all the memory being "seen" by the player, and some very good transfer speeds. I have not yet specifically tested the actual speed, but will do so soon with the Black Magic speed tester, and will update this review with that report.Right now (mid-2018) this card is running at just under $200. I don't suspect it will drop anytime soon, since its the only guy on the block, so if you have a use for it, you might as well get it now. I doubt this will even be marked down much towards the end of the year, although I could be wrong, due to its unique status. Having said that, if the price is still too high, keep an eye on it, because there MAY be occasional rebates, two-day sales, etc.It has all the standard SanDisk hallmarks: high quality, nice look, good performance, nice looks, and it, of course, comes with an adapter in case you wish to use this in a camera that takes the standard sized SDXC cards. I can put almost my entire lossless audio library on this one card, which is amazing. Five stars, and an update soon with the results of the speed test I plan to perform.