Hello @foxmate57, Welcome to Connect. While we wait for @raebaby to share what type/model/manufacturer of the TENS unit they use, I thought I would let you know there is another discussion on TENS units where members have shared their experience.
--- TENS Units: https://connect.mayoclinic.org/discussion/tens-units/

I only have numbness with my idiopathic small fiber peripheral neuropathy. When I first started looking for things that might help, I purchased a Zopec DT-1200 Tens Unit for PN and used it for about 6 weeks but it didn't help with my neuropathy but others in the Minnesota Neuropathy Association where I learned about the device thought it helped them - https://www.zopec.com/products/zopec-electrotherapy-for-neuropathy-and-pain.

Have you used a TENS unit before?