Your search for "QSFP28" revealed the following:

nVidia Mellanox MCP1600-E001E30 1m (3ft) 100GB QSFP28 Passive DAC Cable

SKU: NSB-4592
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Cisco UCS-FI-6454-U UCS 6454 18x 25G SFP28 2x 100G QSFP28 Fabric Interconnect

SKU: NSB-6665
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Extreme VSP7400-48Y-8C 48x 25GB SFP28 8x 100GB QSFP28 No Fans No PSU Switch

SKU: NSH-8529
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Nvidia Mellanox MCX416A-BCAT ConnectX-4 2x 40/56GB QSFP28 PCI-E3x16 Card

SKU: NSB-2873
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Juniper QFX5200-32C-DC-AFO 32x 100G QSFP28 Front-to-Back Airflow (DC) Switch

SKU: NSN-3631
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Juniper QFX5210-64C-AFO 64x 100GB QSFP28 F-B Airflow Switch

SKU: NSN-3636
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Juniper QFX5110-48S-DC-AFO 48x 10GB SFP+ 4x 100GB QSFP28 F-B Air (DC) Switch

SKU: NSN-3623
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Juniper QFX5210-64C-AFO2 QFX5210 Series 64x 100GB QSFP28 F-B Airflow Flex Switch

SKU: NSB-3894
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Juniper QFX5210-64C-DC-AFI 64x 100GB QSFP28 B-F Airflow (DC) Switch

SKU: NSN-3637
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Arista DCS-7800R3-48CQM-LC 48x 100GB QSFP28 w/ MACsec Router Line Card

SKU: NSB-0973
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days