Ted,it looks like a PME 45-very,very expensive-$1000 +.Kiev make 45 degree prisms that fit hasselblads,you can get these for less than $50,the Kievs meters are nowhere near as accurate as Hasselblads-but you may meter handheld anyway.You can even get older model Hasselblad brand,non metered,45's for around $50 too.