zhongsir Original Extreme PRO 4GB CF Card Memory Cards UDMA High Speed CompactFlash

Most excellent.

The Zhongsir 4GB "Extreme" carries a VPG-20 marking, which is intended to be a guaranteed minimum WRITE speed of 20MB/s, in order to support video recording. It didn't come close. The absolute best READ speed I could get out of it was 19.7MB/s, and that was connected over ATA with UDMA enabled. A more realistic connection over USB3.0 in an adapter that I know to be capable of more, was only around 16MB/s, again that was for reading, the writes were slower. The description disagrees with itself, variably calling it a "VPG-65" card, but also "133x". When speeds are listed as "x", it represents the read speed as a multiplier of the original CD-ROM speed of 150KB/s, and wouldn't you know it, 133 x 150KB/s = 19.95MB/s. Almost exactly what this card tops out at with a UDMA connection. If you're expecting it to be a competitor for a genuine "Extreme" card from the maker that originated the moniker and color scheme, (or the fast cards from the other maker whose rainbow color scheme is on the back) expect to be disappointed. It can't match an Extreme III from 2004, or get even half-way to an Extreme IV from 2006, let alone the current versions. It does check out for capacity, and it is just barely acceptable for a 133x card, but until they change the sticker on the card to represent the true specs, I can't recommend it if you actually need a fast, modern card.

Fast ship great product

The 4GB CompactFlash memory card feels like a step back in time, given the more modern storage options available today. However, understanding that some professional cameras still utilize this format, I saw the value in having one as a backup.Four gigabytes isn't a substantial amount of space, especially for shooting high-quality RAW images. It's quite limited in that regard. In a pinch, it's better than not being able to take photos at all, but it's not ideal for extensive photography sessions.The card's read and write speed is acceptable, though not as fast as my SD card. This aspect didn't bother me much since I don't rely heavily on this card. It's more about having an extra option available. The functionality is there—it works as intended, and that's a key point.Pricing would be a significant factor in my overall satisfaction. If the card were expensive, I might feel differently, but as a relatively low-cost item, it's easier to view it favorably.I'm torn between a three and a four-star rating. My practical side says three, considering the limited storage capacity and somewhat outdated technology. But there's an element of appreciation for its reliability and function, which leans towards a four. Balancing these perspectives, I'll settle on a three-star rating, recognizing its utility despite its limitations.

Works great in my Canon EOS camera. I take pictures of merch in my shop and pictures of tattoo work I do. My card reader has no problem reading the card or putting the images on my laptop. Very reasonably priced. I recommend this item.