Ultraman Jack will be the latest Figuart Ultraman figure released. Like all the others, this one will come with a ton of accessories, including the Ultra Spark, Ultra Cross, Ultra Lance, and Ultra Bracelet. There have been many Ultraman releases from Tamashii Nations, he certainly is a favorite of theirs. Basically anything related to robots and kaiju is A-OK with me.
The figure was revealed in the latest Figure Oh-magazine. It will retail for 5940¥. They have been releasing more of these for the 50th anniversary of Ultraman since 2016. I am not as up with all of the differences between the various Ultraman versions as most people are, but this helpful guide from the Ultraman Wiki is helpful:
While nearly identical in appearance to the original Ultraman, the red pattern on Jack's silver suit is slightly different, and he can be distinguished by his shorter "pants," fuller "sleeves" and "knee pads," and pinstripes along the red areas.
Jack is one of the few Ultras who does not require a transformation device. Hideki Goh, the human host for Jack, simply raises his hands to transform at will when Jack signals him to do so, or sometimes even against his will in a very desperate situation. Also, there are times when Hideki Goh tries to transform, only to have the process blocked due to Jack refusing to transform under the circumstances.
Look for Jack in stores in April of 2018. I would imagine Big Bad Toy Store and such will be your best bet to get your hands on one, although sometimes Diamond offers them. You could also check and maybe even preorder one through your local comic book shop.