Taramps Automotive Digital Voltmeter And Sequencer Vts 5.1 Blue Led, Black Product Details All functions are accessed by pressing the FCN key, sequentially. The activation of mixers and/or audio processors should preferably be done at the S1 output for a correct sequential activation (when switching on, from S1 to S5 and when switching off, from S5 to S1), thus avoiding unwanted transients when switching on the amplifier (popularly known as "pop"). IMPORTANT: Outputs S1 to S5 are intended only for activating (REMOTE input) of the sound equipment. Voltage Check: With the VTS 5.1 without the remote signal it is possible to check the voltage of the batteries, press FCN and the voltage will be displayed and whenever you want to turn off the display press FCN again. Function SPL:Press FCN for about 10 seconds until ?SPL? and ?On? appear. This function increases the overvoltage protection (default = 16.5V) to about 19.5V. To deactivate this function, press FCN again for 10 seconds, until ?SPL?and ?OFF?appear on the display. Payment We accept PayPal and credit cards via PayPal. Taxes - US We collect sales tax, as required by law. Shipping We make every effort of shipping within 3 business day of payment clearing. The estimated delivery time is 2 - 5 business days from the shipping date. Policies If you do need to return your item, please contact us via email (you will receive an email when your product ships with additional details - Subject: Important information about your purchase). You will then be provided with a return shipping label and packing slip. Pack the item carefully. Include the packing slip, apply the shipping label, and return the item within 30 business days of the date you request a return, or your return will be canceled. Once we receive your order we will inspect the return. Please allow up to 5 business days of receiving the returned item for your refund.