Auto Meter Z-Series Black 2-5/8 inch (66.7 millimeter) 5000 RPM Mini Tach/Diesel Tachometer Gauge are mountable in every conceivable position and the versatility and durability of the Pedestal Mount tachs have made them a race proven favorite for over 30 years. These tachs offer a variety of performance oriented options from shift lights to memory recall functions, coupled with a trade marked aluminum and rubber shock strap design for the best vibration protection available. A small inductive probe straps to the alternator.