sentences:  On August 28, he took a stock 3-litre model to the track where he made an attempt on the "Double Twelve" record (24 Hour runs were not allowed at Brooklands due to the noise).The car broke before he could achieve that goal but, in the process, Duff set new Class E world records for 1, 2, and 3 hours, 100 and 200 miles, and 100, 200, 300, and 400 km.Duff returned to Brooklands on September 27–28, driving both 12 hour shifts singlehanded to take the Double 12  at an average of 86.52 mph, for a total distance of 2,082 miles (3,351 km).