Your search for "qsfp28" revealed the following:
Dell S4112T-ON-RA 12x 10GB Copper 3x 100GB QSFP28 B-F Air DC OS10 Switch
SKU: NSB-1989
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
NEW Nvidia Mellanox MCP1600-C003E26N 3m 100GB QSFP28 Direct Attach Copper Cable
SKU: NSN-8575
Condition: New
Shipping: Overnight Options
Warranty: 365 days
Dell S5232F-ON EMC S 32x 100GB QSFP28 2x 10GB SFP+ F-B Air No OS10 Switch
SKU: NSB-9764
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
NEW Dell N3248TE-ON 48x 1GB RJ45 4x 10GB SFP+ 2x QSFP28 F-B Air OS6 Switch
SKU: NSN-9969
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Extreme VSP7400-32C-AC-F VSP 7432CQ-F 32x 100G QSFP28 F-B Airflow Switch
SKU: NSN-3548
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Nvidia Mellanox MCP1600-C01AE30N 1.5m 100GB QSFP28 Direct Attach Cable
SKU: NSN-8574
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Mellanox MFA1A00-C010 10m 100GB QSFP28 Active Optical Cable
SKU: NSN-8616
Condition: New
Shipping: Overnight Options
Warranty: 365 days
Cisco N540X-16Z4G8Q2C-D 16x 10GB SFP+ 8x 25GB SFP28 2x 100GB QSFP28 Router
SKU: NSB-0638
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
Nvidia Mellanox MSN2010-CB2F 18x 25GB SFP28 4x QSFP28 B-F Air (P2C) Onyx Switch
SKU: NSB-6773
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
Juniper QFX5200-32C-DC-AFO 32x 100G QSFP28 Front-to-Back Airflow (DC) Switch
SKU: NSH-8255
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days