Twofold Cantor sets in $\mathbb{R}$

A symmetric Cantor set $K_{pq}$ in $[0,1]$ with double fixed points 0 and 1 and contraction ratios p and q is called twofold Cantor set if it satisfies special exact overlap condition. We prove that all twofold Cantor sets have isomorphic self-similar structures and do not have weak separation property and that for Lebesgue-almost all $(p,q)\in [0,1/16]^2$ the sets $K_{pq}$ are twofold Cantor sets.