Manufacturer functional interchange
Toledo Gear TQ18 appears in the same manufacturer-published cross-reference row as Winsmith 917MDN at Match installed ratio · 1.75 in center distance.
Toledo Gear publishes TQ18 at 1.75 in center distance for c-face input / shaft output and lists the competitor models in the same TG-90 interchange row. Toledo describes TG-90 reducers as designed to be functionally interchangeable while requiring current rating and dimensional verification.
The manufacturer describes the target family as functionally interchangeable with the listed competitor model or configuration.
Winsmith 917MDN and Toledo Gear TQ18 are tied by the published source at Match installed ratio · 1.75 in center distance.
The source still requires ratings, dimensions, ratio, fit, and application conditions to be checked before ordering.