I say, and with God's success: It is sufficient for him if the area of the length and width of three fingers of the hand or more becomes wet, and the wetness is on the surface of the front of each foot; because the condition is that the water reaches the place that is supposed to be wiped, and this can be achieved without the fingers: such as wiping it with a cloth or pouring water on it. Refer to: رد المحتار 1: 181, وشرح الوقاية ص116, ودرر الحكام 1: 36, والمراقي ص168, and God knows best.