ORIGINAL: mobow
I don't know every arrow size out there, but I've never heard of a 2020....2018 I have..... I would think a 2018 insert would fit though.....I've been wrong before though.
You probably never heard of them because "you just a young pup". Still "wet behing the ears".
OK, I had some fun. Back in the 60's and 70's 2020 shafts were fairly common, as were 1920, 1820 and .018 walled shafts. .016 walls were the shaft of choice if you were looking for speed. Maybe you can tell by my statements that I've been around and seen some incredible evolvement in archery. You rarely even see .018 walls any more.