The designs are reminiscent of classic striped t-shirts of the 1960s. The kind of thing Levi’s Vintage reproduce from its archive now and again.
Each is a soft cotton jersey with a ribbed crewneck, rounded off with a split hem. Keeping things simple definitely works. No logos either, except for the label in the collar, obviously.
Sadly, these are in a minority of items now in the End Clothing Sale, so full price sadly. That’s £55 each.