The Tokina RMC 70-210mm f/4.5-5.6 was an earlier, slower sibling to Tokina's later SZ-X 70-210mm f/4-5.6, produced during the late 1970s and 1980s as a budget manual focus telephoto zoom for 35mm SLR photographers needing portrait and telephoto reach.
It uses a one-touch or two-touch push-pull zoom-and-focus barrel with a manual click-stop aperture ring and RMC-era multi-coating. Maximum aperture falls from f/4.5 at 70mm to f/5.6 at 210mm, modest figures that keep the lens light for its focal range.
Sharpness is acceptable through the middle of the zoom range and softens toward 210mm wide open, with contrast that holds up reasonably in good light but fades in overcast or backlit conditions, typical of consumer telephoto zooms of this generation.
Secondhand examples are common and cheap across most manual SLR mounts. Buyers should check the zoom-focus barrel for grease-related stiffness or looseness, confirm the aperture blades close cleanly, and inspect for haze on long-stored copies.