The 50H82 is the latest model. Tosh 16:9 RPTVs comes in 42", 50", 57" & 65" models -- standard 'H' series & the pricier 'HDX' series. Have a look here & here.
The first 2 digits are the screen size An 'H' means HDTV A 'D' means DVI digital input An 'X' means Cinema Series '8' is the 'feature code' - in this case 'widescreen' Last digit is the year code ('1'=2001, '2'=2002)