What Is called this clock in Chinese? We use this at wall.

Over here, we call this a 牆鐘 (wall clock).  Never ever buy a clock as a gift to a Chinese person!  It is homophonous with 終 = terminal, the end, demise and 送 "to present".  Thus 送鐘 has the same sound as 送 終 "attending your funeral".  A watch 錶 is OK since it has a different sound.  There is a entire array of what kind of gifts are appropriate.  Sending pears is good because 送梨 sounds like  送利 sending you advantages/profits