ModelSLR Magic Anamorphot 1.33x, 50 wide angle adapter 
with 49mm, 52mm and 58mm step-up ring.
Rear thread size           62mm
Front thread size77mm
Min focusing distance   Set at "Normal" about 3 meters (it is taking lens dependent)
ModelSet at "Near"     about 1.5 meters (it is taking lens dependent) 



SLR Magic Achromatic Diopters:
+0.33  : Focus at 3meters, increase clarity, but infinity cannot be achieved.
+1.3    : Focus at around 0.7 meter, but infinity cannot be achieved.