It is 2 bets. One is a win treble where all of the horses must win. This is the one with odds of 845.00. The other bet is an E/W treble, where all of the horses must be 1st, 2nd, 3rd (or 4th if a big race) but the odds on this will be much shorter (something between about 6.00 and 13.00 depending on the E/W terms).
Hope this helps
