Your search for "qsfp28" revealed the following:
NEW Dell S5296F-ON-RA 96x 25GB SFP28 8x 100GB QSFP28 B-F Air (With OS10) Switch
SKU: NSN-8139
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Dell 407-BBTE 15FMD S6100-ON 8x 100GB QSFP28 Switch Module
SKU: NSN-0679
Condition: New
Shipping: Overnight Options
Warranty: 365 days
Dell S5224F-ON 24x 25GB SFP28 4x 100GB QSFP28 Front-to-Back Air OS10 Switch
SKU: NSH-9621
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
Dell Q28-100G-SWDM4 X7CCC 100GB BASE-SWDM 850nm MMF QSFP28 Transceiver
SKU: NSB-5959
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
Dell S4128T-ON-RA 28x 10GB Copper 2x 100GB QSFP28 B-F Air 210-ALTI OS10 Switch
SKU: NSB-6541
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
Dell S4128T-ON-RA 28x 10GB Copper 2x 100GB QSFP28 B-F 210-ALTI (No OS10) Switch
SKU: NSB-9747
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
Dell S5232F-ON-RA 32x 100GB QSFP28 2x 10GB SFP+ Back-to-Front Air OS10 Switch
SKU: NSB-6589
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
NEW Juniper QFX5120-48Y-AFI 48x 25GB SFP28 8x 100GB QSFP28 B-F Airflow Switch
SKU: NSN-3626
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Dell S4128T-ON 28x 10GB Copper 2x 100GB QSFP28 F-B Air 210-ALTC OS10 Switch
SKU: NSN-1905
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Dell S5224F-ON 24x 25GB SFP28 4x 100GB QSFP28 F-B Air No OS10 Switch
SKU: NSN-9948
Condition: New
Shipping: Overnight Options
Warranty: 365 days