Your search for "qsfp28" revealed the following:

NEW Dell S4112T-ON-RA 12x 10GB Copper 3x 100GB QSFP28 B-F AC (No OS10) Switch

SKU: NSN-9955
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Dell N3248P-ON-RA 48x 1GB PoE RJ45 4x 10GB SFP+ 2x QSFP28 B-F OS6 Switch

SKU: NSN-9976
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Extreme 10410 0.5m 100 Gigabit QSFP28 Direct Attach Copper Cable

SKU: NSB-4918
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Dell Z9264F-ON-RA EMC Z-Series 64x 100GB QSFP28 Back-to-Front Air OS10 Switch

SKU: NSB-7049
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Juniper ACX6360-OR-AC 20x 100GB QSFP28 8x 200GB CFP2- DCO F-B Air Router

SKU: NSH-8437
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Cisco C9500-32C-E Catalyst 9500 32x 100GB QSFP28 Front-to-Back Air Switch

SKU: NSN-3657
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Juniper EX4650-48Y-DC-AFI 48x 25GB SFP28 8x 100GB QSFP28 B-F Airflow

SKU: NSH-8961
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Nvidia Mellanox MSN2410-BB2F 48x 10GB SFP28 8x QSFP28 B-F Air Onyx Switch

SKU: NSN-9264
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Nvidia Mellanox MSB7890-ES2R 36x 100GB QSFP28 Front-to-Back (C2P) EDR Switch

SKU: NSB-6792
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Dell N3248TE-ON-RA 48x 1GB RJ45 4x 10GB SFP+ 2x 100GB QSFP28 B-F Air OS6 Switch

SKU: NSB-8628
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days