The big brute of the oyster-shucking world is called a "Galveston knife" (on the left). It's an eight-inch knife with a stout four-inch blade designed for opening large oysters like the five-inch Espiritu Santo Bay oyster shown beside it. (Espritu Santo Bay is down around Port O'Connor.) The knife shown is an inexpensive plastic model available at restaurant supply stores for under $10.
