The present invention relates in a first consideration to aldimines of formula. In some aspects, the method of providing the power tool combo kit provides the economic benefit of purchasing power tools in a combo kit while providing the flexibility of purchasing power tools individually. A current time index is determined based on the timestamp. The first mask is removed and a second mask is formed, leaving predetermined areas of the seed layer exposed. When the two components are brought into close proximity, the two contacts attract each other to mate the contact cores, and thus establish an electrical connection.