Simpson Strong Tie HDU4-SDS2.5 DS83938 Predeflected Holdown, 1 Each Pre-deflected body virtually eliminates deflection due to material stretch Uses SDS screws which install easily, reduces fastener slip, and provides a greater net section area of the post compared to bolts. SDS screws are supplied with the holdowns to ensure proper fasteners are used No stud bolts to countersink at openings Height: 10-15/16 in.