Recommended 16

For product:

Positives:
+ Acceptable price
+ Inside roughened, coated surface
+ Sitting absolutely perfect (18-55mm lens) (not too loose, and Hammerfest not like other products)
+ Works beautifully because of great length

Negatives:
- (For 18-55mm) at 18mm focal length provides you still share the aperture in the pictures (one goes to approx 24mm but they are gone)

Conclusion: Purchase no cheap things that anyway you have to convert only 10 times, so it fits well on the lens, thereby possibly not have such a good quality. I am fully satisfied and would recommend this product only.
Single Mankerl is just the 18mm focal length, but you can fix, too. Therefore, still 5 stars;)

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