rear lens cap for 150 caltar - II N MC

Just purchase a 150 caltar II lens which will arrive with only the front lens cap. Anyone know the size of the rear lens?

thanks -
dave

The Caltar IIN is a twin of the Rodenstock Apo-Sironar-N, so I presume that the barrel of the rear cell is 42 mm in diameter - but it's better to wait for the advise of an owner.

The Rodenstock 150mm Apo Sironar-N uses a 42mm slip-on cap. These are available from Kaiser, 206942 at $10.99 list. Lakeside Camera is a dealer.

Great Thanks - I'm anxious to find out if it preforms like the Sironar Apo, have found many different takes on this lens around the web.