Your search for "QSFP28" revealed the following:

HPE Aruba JL704C 44x 25GB SFP28 6x 100GB QSFP28 F-B Airflow Switch w/ MACsec

SKU: NSB-9590
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Nvidia Mellanox MSN3700-CS2FC 32x 100GB QSFP28 B-F Cumulus Linux Switch

SKU: NSN-9999
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Cisco NCS-5501-SE NCS 5500 40x 10GB SFP+ 4x 100GB QSFP28 Router Chassis

SKU: NSN-9830
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Mellanox MMA1B00-E100 100GB BASE-SR4 850nm MMF MPO QSFP28 Transceiver

SKU: NSN-8606
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Dell N3248TE-ON 48x 1GB RJ45 4x 10GB SFP+ 2x QSFP28 F-B Air OS10 Switch

SKU: NSN-9972
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Cisco N540-ACC-SYS NCS 540 24x 10GB SFP+ 8x 25GB SFP28 2x 100GB QSFP28 Router

SKU: NSB-8197
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Cisco N9K-C93108TC-FX3P 48x MultiGB UPoE RJ-45 6x 100GB QSFP28 BF Air Switch

SKU: NSN-0629
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Extreme EN-SLX-9030-48S-4C 48x 10G SFP+ 4x 100G QSFP28 No Fans No PSU Switch

SKU: NSN-5026
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Arista DCS-7280CR3K-32D4-F 32x 100GB QSFP28 4x 400GB QSFP-DD F-B Air Switch

SKU: NSN-6452
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Nvidia Mellanox MSN4600-CS2FC 64x 100GB QSFP28 B-F Air P2C Cumulus Linux Switch

SKU: NSB-6709
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days