This black water bucket float works in conjunction with dehumidifiers. The bucket float helps monitor the water level within the dehumidifier water bucket to prevent the bucket from over flowing. When the water level reaches the maximum level, the bucket float will signal the switch to stop the dehumidifier to prevent the water bucket spilling on to the floor. If there is water on the floor the water bucket is overflowing, you will need to replace the float. This part is made of plastic and measures approximately 4”. This is a genuine OEM part. Please remember to disconnect the power to the dehumidifier before starting the repair.