M48 Back Focus Spacer Metal washer/spacer, used to adjust back focus and camera angle 11 thickness specifications 11 Specification Models Metal washer/spacer, 11 thickness specifications from 0.02mm to 1mm Material: 304 stainless steel Thicknesses of 11 models: 0.02mm, 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, 1mm Product Uses: 1: Adjust back focus and camera angle. 2: When the phenomenon of excessive infinity occurs during lens modification, resulting in insufficient close - up shooting, precise compensation through spacers makes infinity more accurate. 3: When there is still margin for infinity during lens modification, adjust the orientation of the lens's central axis through spacers.