Portable mini adjustable 4&rdquo; ultra-quite PC USB Cooling Desk Fan Blue with 4 aluminum blades Feel relax while you work for this cooling breeze ultra-quite mini adjustable USB desk fan 4". Four aluminum blades to give you more cool wind than most of the 3 blades fan. Can be adjusted into 360 direction (up and down) to meet your desired and flexible needs. With power switch for ON and OFF usage very convenient, dont need to plug or unplug on your computer USB port. Measurement: 4 of blades and 5.5 of metal frame for your space convenience.