DISCONTINUED ITEM-LTD QTY AVAILABLE This is a set of 3 kits each with a unique approach to timing a relay. 1st Kit- uses a 555 as a stable oscilltor and 14 stage ripple counter and pot to set oscillator frequency 2nd Kit-uses a 555 as a monostable timer and pot to set time. 3rd Kit is a timer based on R/C discharge to control a relay. Kits are 12VDC powered.