How does this mount?

[Paul Steinberg]

How does this mount to the siren? What is it called? thanks

 

[Kurt Arends]

Why is it in your bed?

 

[Daniel Scully]

How does this mount to the siren? What is it called? thanks

Looks like a C section to me.

 

[Richard Vyse]

Silicone and duc tape cures all...

 

[John ED Renstrom]

It mounts no more.

 

[Kevin O'Connell - Deceased - 1954 - 2019]

What are the dimensions? ID, OD, depth and gap...