One 10.5 x 6 inch Happy Grumpy Birthday Tall Centerpiece with assembly instructions. Add some senior style to your tables with our Happy Grumpy Birthday Tall Centerpiece. This centerpiece was designed by Moxzie, Inc. to coordinate with our Happy Grumpy Birthday Party Supplies. The triangular piece is printed on all three sides, and set-up is quick and easy. Use your centerpiece alone, or pair it with our small centerpieces for a perfect matching set.