They were manufactured by R.F.D. Co.Ltd of Gadalming, Surrey, a company founded by engineer Reginald Foster Dagnall. Over time, RFD became a synonym for "Rapid Flotation Devices".
Utilization
For more than 60 years the D-class has served as the workhorse of the RNLI Inshore Lifeboat (ILB) fleet. The D-class is one of the few RNLI types not to feature a rigid hull. The D-class was specifically designed as a light and highly manoeuvrable rapid response craft, especially suited to close shore work.
There were only six D-class (RFD 320) boats in the RNLI Fleet, and all were utilised as Boarding Boats.