A delay line for an ultrasound transducer including: upper and lower surfaces, wherein the upper surface is configured to engage with an ultrasonic transducer and the lower surface is configured to engage with an object to be tested and the upper and lower surfaces have an area that is smaller than an area of the ultrasonic transducer; and at least one attachment face configured to attach to the ultrasound transducer. A method of applying ultrasonic energy to an object, the method including: applying a delay line to an object, wherein the delay line has: upper and lower surfaces, wherein the upper surface is configured to engage with an ultrasonic transducer and the lower surface is configured to engage with an object to be tested and the upper and lower surfaces have an area that is smaller than an area of the ultrasonic transducer; and at least one attachment face configured to attach to the ultrasound transducer; generating ultrasonic pulses via a transducer attached to the delay line; determining measurements based on the ultrasonic pulses; and determining characteristics of the object based on the measurements.