I recently bought a couple of sets of these nice looking 4mm banana plugs, which arrived from Hong Kong with amazing speed. Not only are they fairly sensibly priced, when I put them on my Naim NACA5 cable in place of soldered beryllium copper z-plugs, the sound performance is much improved. So, a clear recommendation from me.
https://www.ebay.co.uk/itm/4x-MC-Aud...kAAOSwSVJacWcC