Your search for "qsfp28" revealed the following:
NEW Dell S4128F-ON-RA 210-ALTF 28x 10GB SFP+ 2x 100GB QSFP28 B-F Air OS10 Switch
SKU: NSN-8121
Condition: New
Shipping: Overnight Options
Warranty: 365 days
Dell S5248F-ON-RA 48x 25GB SFP28 2x 200GB QSFP28-DD 4x QSFP28 B-F OS10 Switch
SKU: NSB-6590
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
Dell QSFP28-100G-LR4 GMFC5 100GB BASE-LR4 1310nm SMF LC QSFP28 Transceiver
SKU: NSH-6164
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
NEW Dell S5296F-ON-RA 96x 25GB SFP28 8x 100GB QSFP28 B-F Air (No OS10) Switch
SKU: NSN-9939
Condition: New
Shipping: Overnight Options
Warranty: 365 days
Cisco N9K-C93600CD-GX 28x 100GB QSFP28 8x 400GB QSFP-DD F-B Airflow (DC) Switch
SKU: NSB-2971
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
NEW Arista QSFP-100G-SWDM4 100GB BASE-SWDM4 70m OM3/100m Duplex MMF QSFP28
SKU: NSN-0315
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Dell S4148F-ON 210-ALSI 48x SFP+ 4x QSFP28 2x QSFP+ F-B Air OS10 Switch
SKU: NSN-1906
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Dell S4128F-ON 210-ALSY 28x 10GB SFP+ 2x 100GB QSFP28 F-B (No OS10) Switch
SKU: NSN-9932
Condition: New
Shipping: Overnight Options
Warranty: 365 days
Juniper QFX5120-48Y-DC-AFO 48x 25GB SFP28 8x 100GB QSFP28 F-B Air (DC) Switch
SKU: NSH-8251
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
NEW Dell S5212F-ON-RA 12x 25GB SFP28 3x 100GB QSFP28 B-F Air OS10 Switch
SKU: NSN-8133
Condition: New
Shipping: Overnight Options
Warranty: 365 days