To..................
Notice is hereby given that we cancel our contract  dated for the sale of (description of goods) to (name of firm ), for the following reason.
That on (date),you breached said contract in the following respest
Cancellation of said contract is effected in respect to that certain installment delivered on (date).and for any subsequent delivery of goods, inasmuch as your breach impairs the contract as a whole
(We claim damages from you in the amount of. $)
Dated:______________
(Signature)