The ornamental design for a distributionboard, as shown and described.
FIG. 1. is a front, right, and top perspective view of a distribution board showing our new design;
FIG. 2. is a rear left, and top perspective view thereof;
FIG. 3. is a front elevation view thereof;
FIG. 4. is a rear elevation view thereof;
FIG. 5. is a left elevation side view thereof;
FIG. 6. is a right elevation side view thereof;
FIG. 7. is a top plan view thereof; and,
FIG. 8. is a bottom plan view thereof.
The broken line showing of a portion of the bottom of the distribution board is for the purpose of illustrating those portions of the distribution board and forms no part of the claimed design.