Small elbow Water Hose as used only on the BMW 2002tii and turbo 1971-74. I believe this goes to the warm-up regulator. Original BMW part. Fits the following models:

114 2002tii SEDAN, U.S. 
114 2000tii TOURING, Euro 
114 2002tii SEDAN, Euro 
114 2002tii TOURING, Euro 
114 2002turbo SEDAN, Euro 

E12 520i SEDAN, Euro