http://tinyurl.com/l9y9kpj
Greenlee 441-4 Feeding Sheave for 4-Inch ConduitProduct Review
Click on the link for more reviews
Yoke frame slides into the end of conduit and holds sheave, allowing the cable being fed into the conduit to smoothly roll over the sheave
5-Inch (127 mm) wide aluminum alloy sheave with self-lubricating bearings
Split tube for easy removal after cable is installed