Your search for "QSFP28" revealed the following:

Juniper ACX6160-T-DC 8x 100GB QSFP28 4x 200GB CFP2- DCO F-B Air (DC) Router

SKU: NSB-5313
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Cisco N540-24Z8Q2C-SYS 24x 10GB SFP+ 8x 25GB SFP28 2x 100GB QSFP28 Router

SKU: NSB-8195
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Ruckus ICX7850-32Q ICX 7850 Series 32x 100GB QSFP28 Switch

SKU: NSN-8072
Condition: New
Shipping: Overnight Options
Warranty: 365 days

EdgeCore 7712-32X-O-48V-B AS7712-32X 32x 100GB QSFP28 B-F Airflow (DC) Switch

SKU: NSB-0622
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

EdgeCore 7712-32X-O-48V-F AS7712-32X 32x 100GB QSFP28 F-B Airflow (DC) Switch

SKU: NSB-0618
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Mellanox MSB7700-ES2F SB7700 Infiniband 36x 100GB QSFP28 EDR B-F Air Switch

SKU: NSN-0627
Condition: New
Shipping: Overnight Options
Warranty: 365 days

HPE JL722C Aruba CX 8360 v2 Series 24x 10GB SFP+ 2x 100GB QSFP28 Switch

SKU: NSB-3811
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

NEW Fortinet FS-3032E 3000 Series 32x 100GB QSFP28 Front-to-Back Airflow Switch

SKU: NSN-8458
Condition: New
Shipping: Overnight Options
Warranty: 365 days

Fortinet FS-3032E 3000 Series 32x 100GB QSFP28 F-B Registrable/Unclaimed Switch

SKU: NSC-0281
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days

Ruckus ICX7550-48F-E2 36x 1GB SFP 12x 10GB SFP+ 2x 100GB QSFP28 F-B Air Switch

SKU: NSB-7426
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days