ToppBolt – Female Concrete Screw in Inch Sizes
Direct-fastening concrete screw with a female head in inch sizes – with the American ESR approval.
What is the ToppBolt?
The ToppBolt is a direct-fastening female concrete screw in inch sizes. Like the rest of the concrete screw family, it cuts its own thread straight into the walls of the drilled hole and forms a mechanical lock – with no plug and no chemical resin.
The key difference: the ToppBolt carries the American ESR approval (rather than a European ETA), and it comes in inch sizes. It is the solution when the project specification or the equipment on site is built to American standards.
Technical Specification
| Characteristics | Direct-fastening concrete screw, female head |
| Sizes | Inch |
| Steel | Grade 7.8 |
| Corrosion protection | Zinc plated (hot-dip galvanized to order) |
| Technology | Direct fastening |
| Cracked concrete | Yes |
| Seismic loads | Yes – categories A-F |
| Approvals | American ESR approval for cracked and uncracked concrete and for seismic loads |
When to Choose the ToppBolt
American specification
When the project is designed to American standards and an ESR approval is required rather than an ETA.
Inch sizes
When the equipment, hangers or threaded rods on site are imperial rather than metric.
Female head
The suspended element threads into the head and is installed after the anchor – and can be replaced without touching the anchorage.
Seismic loads
Approved for seismic categories A-F.
Need a female head in metric sizes? See the TFF female-head concrete screw, which carries the European ETA1 and ETA6 approvals.
The Rest of the Concrete Screw Family
Files to Download
Frequently Asked Questions
What is the difference between the ToppBolt and the TFF?
Both are direct-fastening concrete screws with a female head. The difference: the ToppBolt comes in inch sizes and carries the American ESR approval; the TFF comes in metric sizes and carries the European ETA1 and ETA6 approvals. The choice depends on the project specification and the equipment on site.
What is an ESR approval?
The ESR (Evaluation Service Report) is the American approval for anchors, equivalent to the European ETA. The ToppBolt carries ESR-4376, approving its use in cracked and uncracked concrete and under seismic loads in categories A-F.
Is the ToppBolt available hot-dip galvanized?
Yes – hot-dip galvanizing is available to order. The standard version is zinc plated.
Can the screw be removed and re-installed?
Yes. Like the whole direct-fastening concrete screw family, the ToppBolt can be removed and re-used.