A seal assembly (100) is provided, which is used to seal the connection region between a glass (103) and a shaft assembly (108) passing through the glass (103). The shaft assembly (108) may comprise a shaft (113) and a threaded bushing (114) around the shaft (113). The seal assembly (100) may comprise an outer seal (101), which has a body portion (115) supported on the glass (103), and further comprises at least one sealing portion (116) to form at least one sealing area (119, 121); and the seal assembly (100) further comprises an inner rotatable seal (106), which has a body portion (122) with a thread (128) for engaging a thread (110) of the bushing (114), and which further comprises at least one second sealing portion (123) to form at least one sealing area (124). Therein, the body portion (115) of the outer seal (101) and the body portion (122) of the inner rotatable seal (106) have corresponding threads (102, 107) for engaging the outer seal (101) with the inner rotatable seal (106). The assembly (100) can prevent the water leakage at the connection region between the wiper and the vehicle body effectively. The assembly (100) is easy and convenient to be installed, with high reliability, and has an advantage in appearance.