That is a kit to add to a TI distributor to make a system up,[coil,amp and plate and wiring] coil numbers varied. Ive seen all kinds with #d coils While in essence it can be considered a zl1 setup it doesnt vary from other TI setups that used a certain coil #,all TIs were basically the same,its an OTC kit. If you sign up as a paid member the next [third]question gets answered free too .