iso

I can’t work out which compression elbow has been used. I’ve only removed the sink waste elbow, but it revealed a 45mm pipe - 1 3/4 inch-ish I guess. All I I can find, though, are McAlpine ISO 1 1/4”, 1 1/2” and 2” elbows. I’m a bit stumped, to be honest. Any help would be appreciated. Thanks.