There is a bit of controversy about the Circulation Booster. I do not see how it can actually work. It appears to electrical stimulate muscles to help pump blood back to the heart. Going for a walk walk do the same thing and be substantially better for you. It may help with the pooling of blood and fluid around the ankle and some of the research suggests that this might potentially lower the risk for a DVT, but so will going for a walk do the same thing! The advantage of walking is that this can improve the arterial circulation, which is the circulation that gets down to the foot and lower limb and the Circulation Booster does not affect that.

Have a look at these opinions:
https://podiatryarena.com/index.php?threads/circulation-boosters-good-or-bad.37534/
https://podiatric.blogspot.com/2011/09/does-circulation-booster-work-at.html
https://podiapaedia.org/wiki/peripheral-vascular-disease/treatment/circulation-booster/
https://croydonfoot.com/do-circulation-boosters-really-work/
https://themedicaldispatch.com/cricket-legend-believes-revitive-circulation-booster-has-helped-him-feel-better/

There is a lot of controversy around the Circulation Booster - mainly the lack of evidence for the claims that they have made for it. Several advertising authorities have taken them to task over this.