Here's what we see in the 1977 catalog (below) -- http://www.onthedash.com/document/1977-catalog/

and then the 1978 catalog (below) -- http://www.onthedash.com/document/1978-catalog/

and then the 1981 catalog (below) -- http://www.onthedash.com/document/1981-catalog/

So the style for the strap seems to be the "Tropic", plastic strap . . . what people call the "racing" strap, with the large holes.

I will need to check through some photos to see whether I have any showing the Monza on its original strap. I can't recall seeing any such photos.

Jeff

++++++++++++++++++++++++++++++++

: Hi
: Would anyone be able to help me find out what strap was fitted to
: my Monza black coated 150.501?
: I bought it with a solid black leather one but suspect it
: originally had a rally version but photos are confusing.

: Many thanks