I have a m 110mm SWD U-bend connection in close proximity to the underside of a floor slab. The measured clearance is 50mm depth and therefore, I can unable to install your standard collar (200 or 400 series).

The functional height of both the 200 andn400 series collars are 60mm, for applications outlined above we recommendninstalling our Pyroplex 200 series SL collars for this application as thenoverall measured height of a 110mm measures nominal 30mm overall depth. Furtherninformation can be obtained by referring to the Technical Data Sheet.