<https://vilros.com/products/raspberry-pi-4-fan-case#Product>
<http://schema.org/description>
"This listing is for the FAN ONLY and Does NOT include the official Raspberry Pi 4 Case.The case must be purchased separately.\n-----------------------------------------------------------------\nRaspberry Pi 4 Case Fan. Designed for overclockers and other power users this fan keeps your Raspberry Pi 4 at a comfortable operating temperature even under heavy load.\nFeatures:\n\nFits perfectly into the lid of the Official Raspberry Pi 4 Case.\nTemperature-controlled fan delivers up to 1.4 CFM of air flow over the processor, memory, and power management IC.\n18 mm × 18 mm × 10 mm heatsink with self-adhesive pad improves heat transfer from the processor.\nBundled 18mm × 18mm × 10mm heatsink with self-adhesive pad improves heat transfer from the processor.\n\nTemperature-controlled fan delivers up to 1.4 CFM of airflow over the processor, memory, and power management IC.\n\n"
<https://vilros.com/collections/raspberry-pi-fans>