The short form designation for 737 aircraft changed slightly when the 700 was put into service by Boeing. To call that one "737" would have caused much confusion so the three character designation was altered to 73G (G being the seventh letter of the alphabet). In natural progression, the 800s are sometimes shown as 73H. Therefore, what you are looking at is a standard issue Delta 737-800 altho some have maintained that when DL uses the 73H, it signifies that the aircraft has been fitted with AVOD.