  We compute the power in the lowest multipoles of CMB anisotropies in the
presence of radiation-like solid, a hypothetical new kind of radiation with
nonzero shear modulus. If only the ordinary Sachs-Wolfe effect is taken into
account, the shear modulus to energy density ratio must be in absolute value of
order $10^{-5}$ or less for the theory to be consistent with observations
within cosmic variance. With the integrated Sachs-Wolfe effect switched on, the
constraint is relaxed almost by two orders of magnitude.
