The geometry arising from Michelson & Strominger's study of =4<i>B</i> supersymmetric quantum mechanics with superconformal <i>D</i>(2, 1; )-symmetry is a hyperKhler manifold with torsion (HKT) together with a special homothety. It is shown that different parameters are related via changes in potentials for the HKT target spaces. For 0, 1, we describe how each such HKT manifold <i>M</i> <sup> <i>4m</i> </sup> is derived from a space <i>N</i> <sup> <i>4m4</i> </sup> which is quaternionic Khler with torsion and carries an Abelian instanton.