What is the difference between the Arcteryx...
What is the difference between the Arcteryx Theta SL and the Theta AR womens shells?
The Theta AR is built with Gore Tex Proshell, which gives it better breathability, and it's also built with a more durable face fabric. Paclite is used in the Theta SL, which makes the jacket lighter. Also a bit of difference in patterns, the Theta SL is a bit more trim, as it's intended use is for less severe weather.