Your search for "QSFP28" revealed the following:

Extreme Brocade BR-SLX-9240-32C-AC-F 32x 100GB QSFP28 F-B Airflow Switch

SKU: NSB-4670
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Arista DCS-7260CX3-64-R 64x 100GB QSFP28 2x 10GB SFP+ B-F Airflow Switch

SKU: NSN-0676
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Arista DCS-7050SX3-48C8-F 48x 10GB SFP+ 8x 100GB QSFP28 F-B Air Switch

SKU: NSN-0142
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Arista DCS-7170-64C-R 7170 Series 64x 100GB QSFP28 B-F Airflow Switch

SKU: NSN-7024
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Arista DCS-7280CR3K-32D4-R 7280R3 32x 100GB QSFP28 4x 400GB QSFP-DD BF Switch

SKU: NSB-4709
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Ruckus ICX7550-48F 36x 1GB SFP 12x 10GB SFP+ 2x 100GB QSFP28 F-B Airflow Switch

SKU: NSB-7420
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Nvidia Mellanox MSN2700-CS2F 32x 100GB QSFP28 B-F Air (P2C) Onyx Switch

SKU: NSN-9261
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Cisco N9K-C93240YC-FX2 48x 25GB SFP 12x 100GB QSFP28 F-B Airflow Switch

SKU: NSN-8186
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Arista CCS-720XP-48ZC2-F 48x MultiGB PoE RJ45 4x SFP28 2x QSFP28 F-B Switch

SKU: NSN-4101
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Ruckus ICX7550-24ZP 12x 2.5GB PoE+ RJ45 10GB PoE+ RJ45 2x 100GB QSFP28 Switch

SKU: NSB-7416
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days