Husqvarna 2009 TE 310 Workshop Manual page 364

"KIT" ASSEMBLING INSTRUCTIONS
"DUAL MODE" BUTTON ASSEMBLING (TE)
Dual mode button 8000H0590
The "dual mode" button allows to select the correct map according with the
ground conditions (knob in rest position to select dry ground map- SEL 1 on
instrument display; push knob to select wet ground map- SEL 2 on instrument
display).
O.32 Part. N. 8000 H0368 (09-2008)