Any offer like this it is best to email the bookie direct and ask them to clarify the terms as quite often they can be ambiguous.
Some bookies would say win only was an outright bet, so Man Utd to win the league, Tiger woods to win the US Masters etc.
Other bookies would say a win only was to win a match, so Man Utd to beat Fulham or Tiger Woods to win his 3 ball.
Finally win only could just mean any bet that results in a win or a loss, so not Asian Handicaps or Draw No bet where a push is possible
"All you need to ask yourself is do you feel lucky? Well do you......Punk!"