Manufacturer page.

Built with identical tubular assemblies, the 8T both fit standard door preps. The 8T is often paired with a cylindrical lock in commercial office spaces, residential applications and other spaces where there is a greater need for security and, more specifically, a deadbolt that is more resistant to brute force attack. The 8T is also available with lead line options, making it a good solution for radioactive doors (MRI, x-ray, etc.) in healthcare facilities.