Your search for "MLX-40Gx4" revealed the following:

Extreme Brocade BR-MLX-40Gx4-M ExtremeRouting MLX 4x 40GB QSFP+ Router Module

SKU: NSH-4776
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Extreme Brocade BR-MLX-40Gx4-M 4x 40GB QSFP+ Router Module

SKU: NSN-2651
Condition: New
Shipping: Overnight Options
Warranty: 365 days