Easy to Install
Theft-Proof Locking Device
CRL No-Draft Speak-Thrus are designed to
allow audible transmission of voice requests at ticket windows, box offices and
more. They prevent tampering from the outside, and stop drafts to the interior.
The CRL 549 Series is made of brass. Each unit is individually boxed with
gaskets and mounting screws for installation on glass up to 1/4 inch (6.4
For thicker glass up to 3-3/4 inch (95 millimeters), you can
use the optional four inch (102 millimeter) screws Cat. No. 8324.
Speak-Thrus require a minimum hole diameter of 2-1/4 inch (57 millimeters), and
will cover holes up to 4-1/4 inch (108 millimeters).
Recommended hole diameter
is 3-1/2 inches (89 millimeters).
Minimum Hole Diameter: 2-1/4 in (57 mm)
Maximum Hole Diameter: 4-1/4 in (108 mm)
Minimum Order: 1 Each