▁electronic ▁timer ▁is ▁pack aged ▁in ▁a ▁metal ▁en closure ▁when ▁sold ▁to ▁drag ▁rac ers , ▁thus ▁the ▁sl ang ▁term ▁delay ▁box . ▁This ▁timer ▁box ▁is ▁a ▁very ▁accurate ▁type ▁of ▁mon ost able ▁mult iv ibr ator ▁( elect rical ▁engine ers ▁also ▁call ▁this ▁type ▁of ▁mult iv ibr ator ▁a ▁" one ▁shot "). ▁ ▁The ▁timer ▁box ▁acts ▁like ▁a ▁time - delay ▁relay . ▁ ▁Many ▁delay ▁boxes ▁actually ▁have ▁an ▁internal ▁relay ▁to ▁switch ▁output ▁current , ▁but ▁some ▁models ▁have ▁solid ▁state ▁trans istor ized ▁output ▁circ uits . ▁ ▁The ▁trans istor ized ▁type ▁made ▁today ▁almost ▁always ▁use ▁power ▁M OS F ET ▁type ▁output ▁circuit ry . ▁Drag ▁racing ▁delay ▁boxes ▁are ▁designed ▁to ▁operate ▁from ▁the ▁vehicles ▁ 1 2 ▁volt ▁DC ▁elect rical ▁system . ▁Some ▁drag ▁race ▁cars ▁now ▁use ▁ 1 6 ▁volt ▁DC ▁systems , ▁in ▁such ▁a ▁scenario ▁the ▁delay ▁box ▁has ▁to ▁be ▁capable ▁of ▁working ▁properly ▁from ▁ 1 6 ▁vol ts ▁DC , ▁as ▁well ▁as ▁ 1 2 ▁vol ts ▁DC . ▁ ▁The ▁race ▁car ▁driver ▁holds ▁an ▁elect rical ▁push button ▁switch ▁de pressed ▁with ▁a ▁finger ▁or ▁a ▁thumb ▁of ▁his ▁right ▁or ▁left ▁hand ▁until ▁he ▁sees ▁a ▁specific ▁desired ▁visual ▁c ue . ▁ ▁That ▁elect rical ▁push button ▁switch ▁is ▁monitor ed ▁by ▁the ▁delay ▁box . ▁As ▁long ▁as ▁the ▁race ▁car ▁driver ▁holds ▁the ▁push button ▁de pressed ▁the ▁delay ▁box ▁sends