Let β 1 , β 2 > 1 and T i (x, y) = x+i β1 , y+i β2 , i ∈ {±1}. Let A := A β1,β2 be the unique compact set satisfying A = T 1 (A) ∪ T −1 (A). In this paper we give a detailed analysis of A, and the parameters (β 1 , β 2 ) where A satisfies various topological properties. In particular, we show that if β 1 < β 2 < 1.202, then A has a nonempty interior, thus significantly improving the bound from [2]. In the opposite direction, we prove that the connectedness locus for this family studied in [15] is not simply connected. We prove that the set of points of A which have a unique address has positive Hausdorff dimension for all (β 1 , β 2 ). Finally, we investigate simultaneous (β 1 , β 2 )-expansions of reals, which were the initial motivation for studying this family in [5].