The reason why the condition is “AB-” because Lens body has stains trace in patches.
Inside the lens has minute dusts particle, however it is not effect on picture quality.
We confirmed Shutter and Auto Focus and Diaphragm work properly by mounting lens on camera.
There is no problem with working.
See more detail Condition：AB-(Excellent-) Mamiya7 N 150mm f/4.5 L 【 Free Shipping ! 】 【 Free Shipping ! 】 Shipping ! ⇒Jump to Japanese Website.