On 4 October 2016, Homer calls a company known as Pest Patrol and speaks with Christine, a representative, he then outlines his problem and gets an offer of £400 for fumigation services. , which he accepts over the phone. At this point, Homer has agreed to a unilateral contract, in which only one party assumes an obligation under the contract. In this case, the party that assumes an obligation is Pest Patrol and its duty is to provide the fumigation services in exchange for money. An example of this can be seen in the case of Great Northern Railway Co v Witham, where it was held that the claim was allowed because the claimants were not obliged to order materials, but the defendant was obliged to deliver in accordance to his offer. On October 5, 2016, Homer receives contracts from Pest Patrol stating the agreement of £400 for the fumigation service as conditions of the offer. After signing and sending the contracts to Pest Patrol on October 5, 2016, Homer did not receive a response from the company for several days. On October 11, 2016, Homer attempts to revoke his offer with Pest Patrol by sending a letter criticizing their speed and informing the company to rescind his acceptance. However, Homer had already accepted the offer through the postal rule which states that acceptance takes effect once the mail is sent.