I don't have see-thro' trunks, of any make, but I do have tan-thro' ones, made and sold by Kiniki. They are made from a very fine mesh, which with the dark colour scheme makes them opaque to view while letting the UV in.
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I used to have a pair of yellow Speedos (genuine Speedo brand too) that, despite a double thickness panel at the front, were completely sheer when wet.
@voodoo1970 on my Speedos, I always cut out the inner lining in front right away. I added some elastic to the strip of fabric I cut out and made a g string that was very revealing.