1974 - 904 Transmission Reverse/Low Band - ???

That looks like the band used in 6cyl. and 273 cu.in V8 transmissions as it is only a single wrap band(used from 1960-2003).
All other 904 V8 applications used what is called a double wrap band(used from 1968 to 2003). The A500 transmission also used the same double wrap band.