Anchors/1/4" Drop-In Anchor

Drop-In Anchor

1/4" Drop-In Anchor

Quick Answer

A 1/4" Drop-In Anchor needs a 3/8" pilot hole, drilled to 1" minimum, with 1" minimum embedment, torqued to Set with setting tool; 5 ft-lbs max on the bolt.

Pilot Hole

3/8"

Embedment

1" minimum (sits flush with surface)

Torque

Set with setting tool; 5 ft-lbs max on the bolt

Safe Load

235 lbs

Where to Buy

Budget pick

Wensilon Knurled Drop-In Anchor Assortment (Multiple Sizes)

Multiple sizes · 20 or 100-pack · zinc knurled

★ 4.2 (240)

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Required tool

Drop-In Anchor Setting Tool (Multiple Thread Sizes)

1/4"-20 to 5/8"-11 · zinc-plated carbon steel

★ 4.7 (64)

Check price on Amazon

As an Amazon Associate, BuildToolHQ earns from qualifying purchases. Specifications are for guidance only — always verify against the anchor manufacturer's ICC-ES ESR report and local building codes.

Full Specification

Type

Drop-In Anchor

Diameter

1/4"

Available Lengths

5/8" shell

Pilot Hole Diameter

3/8"

Pilot Hole Depth

1" minimum

Embedment Depth

1" minimum (sits flush with surface)

Recommended Torque

Set with setting tool; 5 ft-lbs max on the bolt

Compatible Substrates

Solid concrete only

Load Rating

235 lbs tension safe working load — Ultimate: 939 lbs tension — Ultimate values in 2000 PSI concrete (Confast). Allowable calculated at the industry-standard 4:1 safety factor. — Confast publishes no shear value for drop-in anchors.

Material

Zinc-plated steel, Stainless steel

Removable

No — permanent installation

Best For

✓Lightweight suspended ceilings
✓Pre-set anchoring positions
✓All-thread rod (1/4-20)
✓Electrical conduit hangers

Not For

✗Hollow block
✗Brick
✗Overhead structural without engineer review

How a Drop-In Anchor Grips

A drop-in anchor is an internally threaded steel body that expands when a setting tool drives its internal plug outward against the hole wall. It cannot grip without being set: dropping it in the hole and threading a bolt in is not an installation, which is why the setting tool is a requirement, not an accessory.

Installation Tips

1.Drill a 3/8" hole for a 1/4" drop-in anchor — the oversized hole is intentional

2.Setting tool is mandatory — do not attempt to set by driving the bolt directly

3.Set flush with or slightly below the concrete surface

4.Used with 1/4-20 threaded rod or machine bolt

Frequently Asked Questions

What size drill bit does a 1/4" Drop-In Anchor need?

Use a 3/8" carbide masonry bit, drilled to 1" minimum.

How much weight can a 1/4" Drop-In Anchor hold?

235 lbs tension safe working load. Actual capacity depends on base material strength and embedment — verify against the manufacturer's ICC-ES ESR data for structural work.