Your search for "QSFP28" revealed the following:

NEW Cisco N3K-C3132C-Z 32x 100GB QSFP28 Back-to-Front Airflow Switch

SKU: NSN-7552
Condition: New
Shipping: Overnight Options
Warranty: 365 days

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

SKU: NSH-8328
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Fortinet FS-3032E 3000 Series 32x 100GB QSFP28 F-B Local Management Only Switch

SKU: NSB-1411
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

HPE Aruba JL707C 8360-48XT4C v2 48x 10GB RJ-45 4x 100GB QSFP28 B-F Air Switch

SKU: NSB-9704
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Dell S4148FE-ON 48x 10GB SFP+ 2x 40GB QSFP+ 4x 100GB QSFP28 F-B Air OS10 Switch

SKU: NSH-9213
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Extreme 10401 100GB BASE-SR4 850nm MMF MPO QSFP28 Transceiver

SKU: NSN-6160
Condition: New
Shipping: Overnight Options
Warranty: 365 days

EdgeCore 7712-32X-O-AC-F-US AS7712-32X 32x 100GB QSFP28 F-B Airflow ONIE Switch

SKU: NSB-1672
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

SuperMicro SSE-C3632S 32x 100GB QSFP28 Front-to-Back Airflow Switch

SKU: NSB-7203
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Arista DCS-7280SR-48C6-M-R 48x 10GB SFP+ 6x 100GB QSFP28 B-F Airflow Switch

SKU: NSN-0397
Condition: New
Shipping: Overnight Options
Warranty: 365 days

NEW Nvidia Mellanox MSN2100-BB2F 16x 40GB QSFP28 Back-to-Front Air Onyx Switch

SKU: NSN-9266
Condition: New
Shipping: Overnight Options
Warranty: 365 days