If you're looking for a small exhaust fan for your bathroom, this 4" one is certainly worth a look. You can easily turn it on and off by pulling the hand rope.
Type: Cooling Only Usage: Home Rotation Way: Without Rotation Installation: Ceiling Fan Fan Speed: Other Air supply mode: Rotary Vane Material: Plastic Controlling Mode: Hand Rope Remote Control Function: No Water-shortage Power-off Protection: No Size: <1050MM Wind Type: Standard Wind Max. Power: <20W Reverse Rotating Function: No Timing Function: No Timing Max. Timing Limit: No Timing Voltage (V): 220V Rotary Vane Quantity: 6 Type: Ventilation Fan Certification: CE Technology: Other Application: 10-15㎡ Power Source: Electric Suspender Length: No Suspender Power (W): 12W Color: White Air flow: 120m3 / h Sound Level: 42 dB Fan Size: approx. 150*150mm Fan Hole Size: approx. 105*105mm