Every R4 manufactured today is a clone (copy, using just the name, etc). That is the most important thing you should know. The so-called 1:1 R4 is a copy of the original, speculated to be manufactured off the original designs, yet make no mistake it is a copy/clone. When buying a Flash Kit you may fail to do your research and opt for the most widely discussed brandname, the R4. This may not be a bad thing if you end up buying one of the 3 GBAtemp recommended R4 Flash Kits. 1. R4i Gold (http://www.r4ids.cn) -- supports DSi v1.4.5 / 3DS v7.1.0-14 There are many clones of the R4i Gold. The card itself started out as a side project for those involved with a previous R4 company. Luckily, the team members that split off have proven themselves to be rather talented. They had a Flash Kit working on the 3DS before any other team, and subsequently released updates before anyone else as well. This card is one of 4 that officially supports the Wood kernel (R4iDSN, AK RPG, original R4 -- being the other 3). When buying an R4i Gold it is important to understand that the card has gone through some hardware revisions. To make sure you are getting the latest version, which will dictate DSi/3DS compatibility, buy from a reputable reseller. One important note for this card is the kernel may be hard to find. A recent DMCA letter sent to GBAtemp had us remove anything with R4i Gold in the title, this included translations, patches, and legitimate releases of the kernel that did not pack in the Gateway 3DS exploit. The last official version before the Gateway 3DS clones were released was Wood for R4i Gold v1.62. Important: If the sticker doesn't say "http://www.r4ids.cn" it is a clone and can not be recommended. 2. R4iDSN (http://www.r4idsn.com/) -- supports DSi v1.4.5 / 3DS v7.1.0-14 The R4iDSN is manufactured and supported by the same team as the R4i Gold (http://www.r4ids.cn). It supports the Wood kernel directly, where the R4i Gold requires an official recompile by the team members. What this means is that the R4iDSN receives updated kernel support 1-2 days ahead of the R4i Gold. Both cards are similar quality and builds, yet due to the hype surrounding the R4i Gold, the R4iDSN has remained a lesser-known card. As a result it can be found online for under $10 USD. 3. R4 (1:1 Clone) -- supports the DS Phat/Lite The original R4 design is still manufactured. The original team is long since gone, but the card continues to perform exceptionally well on the DS Phat/Lite. The design of this card is Generation-1 and can not be updated to work on the DSi/3DS. For those seeking to play DS games and Homebrew on the DS Phat/Lite, this card comes highly recommended. The card supports the Wood kernel directly, just like the R4iDSN. However, the R4 1:1 Clone is limited to 2 GB microSD cards. This card has been offered for sale as low as $1 USD and remains one of the cheaper, yet fully supported, Flash Kit options. Important: The original R4 was cloned and copied more than a few times. The 1:1 clone is an old design, it would not make much sense for a company to copy/clone it for resale. Yet, clones could still exist and be offered for sale by lesser known resellers. For more information on Flash Kits, which are recommended, etc, please view the following links. Which Flash Cart Should I Get by Rydian Flash Carts And DSi/3DS Updates by Rydian DS/DSi/3DS "hacking" F.A.Q. by Rydian Retrogamefan Unofficial R4 Kernel Updates by Retrogamefan Wood R4 BUGS and Compatibility Wood R4i Gold Everything with "R4i Gold" in the title was removed thanks to a DMCA letter that assumed every file was related to their Gateway 3DS clone. Wood R4iDSN Wood R4 Please note that supported firmware revision numbers, packaging photos, and download links are subject to change without warning. Use the information in this post as a guide only.