Abstract: Plywood shear panel diaphragms are utilized in building walls and roofs to support against lateral forces such as earthquakes, wind, tornadoes, and hurricanes. Plywood is typically used for the shear diaphragm in wood construction, nailed vertical or horizontal to wood members. When introducing an opening in a plywood shear panel diaphragm, the diaphragm becomes weakened. Shear transfer process is required to maintain integrity in the shear diaphragm at the opening. The strength from the diaphragm is transferred to the openings edges, the top and bottom edges, using blocks between the framing members acting in compression, and the strap, which acts in tension, transfers the support of the diaphragm to opening. When compared to conventional means, the Block Strap apparatus is a better, more accurate, predictable, cost cutting, labor reducing product for providing for shear transfer requirements in typical common wood construction.