In a guarded hot plate, the dimension of the square test plate is 15 cm $\times$ 15 cm. Keeping the temperatures of the test plate and the air at 35$^\circ$C and 20$^\circ$C, respectively, the power losses from the test plate with and without fabric specimen are 16 W and 40 W, respectively. The intrinsic transmittance [W/(m$^2$ K)] of the fabric (rounded off to 2 decimal places) is \underline{\hspace{2cm}.}