This OpenCart related products module will give you unlimited power to relate your products to each other. FEATURES
Relate products in bulk - many at once Related products by price range Related products by category Delete Related products in bulk matching any search criteria
Requires vQmod 2.3+
Installs via the Extension Installer
Old modules compatibility fix for OpenCart 2.3 included. So your older modules (for 2.1 for example) will magically start to work again.
Check the Documentation its a 1 minute read and install process I promise :)