Subal Zoom ring - 4ZNS867 for Sigma DC 17-70/2.8-4 macro OS HSM (Nikon)
For manual focus and manual zoom lens tooth rings must be applied. SUBAL avoids the fastening with screws - and therefore deformation and damage of the lens with precise adjustment.
for Subal ND3 / ND30 / ND700 / ND90