The oblique slot is formed on {HEAD ~ the front surface} and communicates with a chamber of {TAIL ~ the base} 
The oblique slot is formed on { HEAD ~ the front surface } and communicates with a chamber of { TAIL ~ the base }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL