The design consists of the features of shape, configuration, pattern and ornamentation of the two sided crown moulding as shown in the drawings. The drawings show twelve variants. Figures 1 and 2 show the first variant, Figures 3 and 4 show the second variant, Figures 5 and 6 show the third variant, Figures 7 and 8 show the fourth variant, Figures 9 and 10 show the fifth variant, Figures 11 and 12 show the sixth variant, Figures 13 and 14 show the seventh variant, Figures 15 and 16 show the eighth variant, Figures 17 and 18 show the ninth variant, Figures 19 and 20 show the tenth variant, Figures 21 and 22 show the eleventh variant and Figures 23 and 24 show the twelfth variant.Figure 1 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied. Figure 2 is a front side perspective view of the two sided crown moulding of Figure 1 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 3 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied. Figure 4 is a front side perspective view of the two sided crown moulding of Figure 3 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 5 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 6 is a front side perspective view of the two sided crown moulding of Figure 5 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 7 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 8 is a front side perspective view of the two sided crown moulding of Figure 7 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 9 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 10 is a front side perspective view of the two sided crown moulding of Figure 9 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 11 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 12 is a front side perspective view of the two sided crown moulding of Figure 11 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 13 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 14 is a front side perspective view of the two sided crown moulding of Figure 13 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 15 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 16 is a front side perspective view of the two sided crown moulding of Figure 15 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 17 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 18 is a front side perspective view of the two sided crown moulding of Figure 17 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 19 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 20 is a front side perspective view of the two sided crown moulding of Figure 19 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 21 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 22 is a front side perspective view of the two sided crown moulding of Figure 21 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.Figure 23 is an end elevation view of a two sided crown moulding of constant cross section throughout its length having a variant of the design applied.Figure 24 is a front side perspective view of the two sided crown moulding of Figure 23 broken to indicate indeterminate length. The back side view is the same as the front view rotated 180º.