When the apparatus 100 is passed over {HEAD ~ a uneven variable surface} such as a keyboard 10 as shown in FIG 5, each stem 112 extends under gravity so that both high and low points of {TAIL ~ the surface} are reached by the flexible tips 116 
When the apparatus 100 is passed over { HEAD ~ a uneven variable surface } such as a keyboard 10 as shown in FIG 5 , each stem 112 extends under gravity so that both high and low points of { TAIL ~ the surface } are reached by the flexible tips 116
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH