Dick Dick Parja (Transocean Roughneck, Philippines) works next to an 18.5-inch bi-center bit (top, brown bit) that was used to open a 21.5-inch hole in basement for installation of the 16-inch casing in Hole 1256D. The tricone bit (below the bi-center bit) opens a 9 7/8-inch hole that is reamed to 21.5 inches by the bi-center bit.