Technic, Link Tread Wide with 2 Pin Holes : Part 57518 | BrickLink
LEGO® Technic Track Element DARK STONE GRAY (DK. ST. GRAY) - (4494517/ 4566742/6366190/57518)
LEGO Part 4566742 - 88323 - Track Element 5x1.5 Dark Stone Grey | LEGO Bricks, Replacement Pieces and Parts | Worldwide Flat Shipping to US, UK, Australia, Canada, New Zealand, Malaysia | LEGO Singapore
Technic, Link Tread Wide with 2 Pin Holes : Part 57518 | BrickLink