Fotodiox step rings are made of premium grade aluminum with precision. Every ring is inspected to ensure smooth mounting. Every ring is polished and finished with anodized matte surface for professional appearance. This spacing ring allows for a gap between a filter or attachment. This Ring has the same male and female thread size. Adapter Ring Style Spacing Ring Finishing Aluminum Anodized Black Male Thread Pitch Size 0.75mm Manufacturer Fotodiox Warranty 24 Months