Upgrade your reclaimed boxes and bags by adding sturdy wire handles. Use 2-3 mm...

https://lilysuniquethoughtss.urbanvellum.com/posts/jute-twine-wrap-for-wire-handles-what-thickness-looks-right

Upgrade your reclaimed boxes and bags by adding sturdy wire handles. Use 2-3 mm galvanized wire for strong, rust-resistant grips that last. Drill 3-3.5 mm holes for a snug fit that won't tear your materials