Lego® Technic 4x4 Axle with differential lock - a photo on Flickriver
LEGO MOC Front axle with diff-lock by jelly--fish | Rebrickable - Build with LEGO
How to Build a LEGO Technic Differential Lock Mechanism (Very Easy!) (Building Instructions) - YouTube
LEGO Technic axles and chassis – FT-creations
Sariel.pl » 3 Studs Wide Differential Lock
Sariel.pl » 3 Studs Wide Differential Bracings
Self- Locking Brick Moc Technical Parts 35pcs Technical Simple Differential Compatible With Lego For The Boys Kids Toy - Model Building Kits - AliExpress
LEGO MOC Diff Lock by lbrix | Rebrickable - Build with LEGO