The Simpson Strong-Tie HDIA37SS is a Type 304 stainless steel hollow drop-in internally threaded anchor engineered for attaching 3/8-inch threaded rod to support conduit, cables, cable trays, pipe supports, fire sprinklers, and suspended lighting. Featuring a flush-mount expansion design, this anchor performs reliably in both hollow base materials such as CMU and hollow-core plank and solid base materials such as brick, normal-weight concrete, and lightweight concrete - making it one of the most versatile drop-in anchors available for mechanical and electrical suspension applications.

Key Features

• Suitable for suspending conduit, cable trays, pipe supports, fire sprinklers and suspended lighting into concrete
• Expansion design allows HDIA to anchor into CMU, hollow-core plank, brick, normal-weight concrete and lightweight concrete
• Internally threaded anchor allows for easy bolt removal
• Die-cast Zamac 3 alloy shell with Type 304 stainless-steel cone
• Flush-mount installation keeps the anchor seated at or below the surface for a clean, low-profile finish
• Compatible with a dedicated setting tool for consistent, reliable installation in both hollow and solid materials

Specifications

• Model Number: HDIA37SS
• Bolt/Rod Diameter: 3/8 in.
• Length: 1-1/4 in.
• Drill Bit Diameter: 5/8 in.
• Threads Per Inch (TPI): 16
• Shell Material: Die-cast Zamac 3 alloy
• Cone Material: Type 304 stainless steel
• Packaging: Packs of 50 and Cartons of 200
• Country of Origin: China

Approved Applications

• Suspending conduit and conduit racks from concrete ceilings and overhead structures
• Attaching cable trays and wire management systems to concrete or CMU
• Supporting pipe hangers and pipe supports in mechanical rooms and utility spaces
• Installing fire sprinkler drop-rod connections into concrete overhead
• Mounting suspended lighting fixtures to concrete, brick, hollow-core plank, and CMU
• Any application requiring a flush-mount, internally threaded anchor accepting a 3/8-inch threaded rod

Frequently Asked Questions

What base materials is the HDIA37SS compatible with?

The HDIA37SS expansion design allows it to anchor into a wide range of base materials, including CMU (concrete masonry units), hollow-core plank, brick, normal-weight concrete, and lightweight concrete - making it suitable for both hollow and solid substrates.

What size threaded rod does the HDIA37SS accept?

The HDIA37SS is designed to accept a 3/8-inch diameter threaded rod with 16 threads per inch (3/8-16 TPI threading), which is a common standard size used in conduit, cable tray, and pipe support suspension applications.

What drill bit size is required to install the HDIA37SS?

A 5/8-inch diameter drill bit is required to bore the correct hole for installing the HDIA37SS anchor. Using the correct bit size ensures proper expansion and load performance of the anchor.

What setting tool is needed to install the HDIA37SS?

For installation in hollow materials, use the HDIASTH37 setting tool. For installation in solid materials, use the HDIASTS31-37 setting tool. Using the appropriate setting tool ensures the anchor expands correctly and seats flush with the surface.

Note: Product dimensions may differ from picture. Please see the item description above for specifications.