Few month ago I tested GratKit Firefly filament dryer and my main problem was that it couldn't heat up the air to set 70°C. GratKit fixed the problem in mass production and they sent me new product for the testing. According to my measurings, the reach the peak of approx 75°C in 20 minutes.
Old video is unlisted, but you can see it here:    • GratKit Firefly App controlled Filame...  

Product page: https://gratkit.com/collections/filam...

Download results: https://www.mytechfun.com/video/332

Contents:
0:00 Introduction
2:55 Unboxing
4:57 Display, menu
5:56 Application
6:41 Sponge test
9:17 Thermal camera
10:28 Results
12:10 Conclusions

#3dprinting #gratkit