The most notable development was the introduction of a unique winglet positioned just in front of the rear wheels - a previously under exploited area of the car.
Bottas, who took over from Susie Wolff for the second and final day in Spielberg, said the new parts had already produced a step forward in terms of increasing downforce levels - which he believes bodes well for the team's forthcoming home Grand Prix at Silverstone.
"You've probably seen some weird parts on the car - we have plenty of interesting tests here," Bottas told Formula1.com.
"It's all about getting data, trying to understand more where we need to improve the car.
"Everything has worked as expected - with the new parts we have here we have more downforce, and that should help us in Silverstone."
Bottas ended the morning fastest overall on the second day, while Wolff propped up the timesheet in ninth on day one.
Formula1.com and our official Twitter channel, @F1, will bring you the latest news, images and reaction throughout the Spielberg test. Subscribers to the official F1 App can also get regular live updates on the latest testing times from Austria.