The interesting thing about this pressure cooker is the unique design. Selena mentioned the interesting challenge that confronted us at the store of just figuring out how to get the lid off. I was trying to explain to Sandro on the phone how the lid mechanism works, and found it rather difficult. So here's a few (not very good) pictures....
Notice that the steel of the lid is actually curved. It's able to slip into the pot sideways due to the curvature. Once in it can be turned so to top sides of the convex catch under the lip of the pot. A bar which stays across the top of the pot catches on the top side of the lip. The handle then becomes a leaver that when firmly pulled down flattens out the curved surface of the lid until it is al pressed up against the pot's rim from the inside.
The pot is stainless steel (except for an alluminum alloy at the bottom, i think). So it's quite solid feeling. The walls don't need to be as thick as an aluminum based pot (as many pressure cookers use).
Okay, so the description probably is no help, and neither will the pictures be. But, really, it's endlessly fascinating.
What? You want to hear more about pressure cookers? Good grief, you people are insatiable. Well here's an interesting little history of the devices I've copied from the Lagostina (an Italian company) web site... from which you can learn how the miracle of pressure cookers do no less than liberate women! (So they can cook and go to work work. Yay, women!)
The pressure cooker dates back to 1682, the work of Denis Papin who invents the Digester, a double iron cylinder closed by screws and bars that cooks by pressurizing the captured steam produced from the evaporation of liquids. From that moment it steadily evolves and spread throughout Europe. The pressure cooker becomes popular in Italy in the early 1960s thanks to Lagostina. In the years of the "economic miracle" and women's liberation, the pressure cooker becomes a precious ally of women entering the job market.
Over time, the pressure cooker has adapted itself to Italians' lifestyle and eating customs. Its practicality, which means both convenience in the kitchen and time and energy savings, the fact that it leaves the nutritional value of food unaltered, its absolute safety and easy use and maintenance, are just some of the main characteristics of the pressure cooker, universally appreciated by modern consumers.
For a more technical description, see wikipedia.