CB radios don't ground to the earth to work, only to the chassis of the vehicle. Those straps were "Anti Static Straps" designed to dispel the static build up from your car. I don't think they were ever proven to work and people pretty much stopped buying them by the end of the 90s. I think one of their claims may have been "improved radio quality" but they had a lot of weird claimed benefits that were largely marketing.
CypherFTW t1_ja5l3ei wrote
Reply to comment by Kevinsound27 in Been in every car I’ve had since 1986. by 710dabner
CB radios don't ground to the earth to work, only to the chassis of the vehicle. Those straps were "Anti Static Straps" designed to dispel the static build up from your car. I don't think they were ever proven to work and people pretty much stopped buying them by the end of the 90s. I think one of their claims may have been "improved radio quality" but they had a lot of weird claimed benefits that were largely marketing.