helpful, if incredibly firm, erector spinae massage tool!
this tool is a bit on the firm side (the blue one) and is one of those rare tools that actually access the erector muscles very close to the spine in the  way that therapy balls cant quite get to. The inventor of these is a good man, has friendly instructional videos (which I wish had some close ups), and some of the profits go to serve Ukrainian soldiers who have been traumatized by the conflict with the Russians. If for this last reason alone, I'd add these to your therapeutic repertoire!
Rating: 4 stars