Across Flats (Width): 7/16″ (Max 0.437 – Min 0.428) Color (Duplicate): Silver Color: Silver Condition: New Diameter: 1/4″ Drill (Hole) Size: 1/4″ Drive Style: Internal Hex (Allen) Eye Inside Diameter: 1/4″ Head Type: No Head Finish: Zinc Plated Grade: 5 Head Style: Socket Cap Length: 2-1/4 Material (Duplicate): Zinc Plated Steel Material: Steel Other: Listed As Part Number: 2019-002-0002 Pattern: Acoustical Wedge Anchor Product Type: Acoustical Anchors Size: 1/4″ x 2-1/4″ Size System: US Size Type: Regular System of Measurement: Inch Tolerance (IFI): Actual measurements may vary slightly /- depending on production run within IFI Tolerances Weight: 1 lb Wrench Size: 7/16″ Used to anchor wiring to masonry materials such as concrete Installed into pre-drilled holes Non-threaded end is inserted into the whole then struck to expand The “eye” of the anchor has a 1/4″ Diameter Corrosion resistant Not recommended for exterior use A 1/4″ (CR 3) Zinc plated steel Acoustical Wedge Anchor is used to secure or anchor suspended wire to masonry surfaces, typically concrete ceilings.