The chassis were also sold bare in small numbers, minus bodies from the windshield rearward. These bare chassis versions were finished as pickup trucks and convertibles by such Swedish coach builders as Grip, Valbo and Nordbergs. An intreguing bit of trivia for Volvo buffs is that the Duett was the only automobile marketed by Volvo in the United States that boasted a separate frame. All other models were of unibody construction. Use of the separate ladder chassis provided Volvo with an easy solution in their desire to produce a suitable commercial vehicle even though some thought it a regression when pointing out that the basis for the wagon was developed from Volvo's first unibodied car; the PV444 introduced in 1947.
The model number designations distinguishing this family of Volvos are the 445 or P445, and the P210. The most notable difference that readily determines at a glance "which is which" is quite simple. If it's a PV-like estate with a 2 piece flat paned windshield like PV444, the car is a 445. The P210 introduced in the early 1960s sported the single piece curved windshield like it's sister sedan, the PV544.
Use of the name Duett is something of a Swedish pun or play on words. In this context it was intended to give a name to a car that during the week would serve a business owner ably as a delivery vehicle while doubling easily as a comfortable Sedan during "time off".
The final P210 rolled off the line in 1969 having survived the car that spawned it by 4 years. The utility of the car was highly regarded and as a replacement, Volvo produced a highroofed version of the Volvo 145 estate wagon known as an Express. While eagerly sought now by fans of more esoteric Volvos, the Express was something of a disappointment to those who insisted on comparing it to the lamented late Duett.