Bird guard spikes to keep birds off ultrasonic wind sensors.  Suited to the Gill Windsonic sensor, it attaches with industrial strength double sided tape (proven to work for over 6 months in temperatures above 45degC).  100% effective at keeping those pesky birds off the sensor. Made in ABS, 0.2mm, no support but you may want to try using a brim if you get lifting off the bed.