This is Hornby's Number 1 speedboat: according to the leaflet it can be used in either the bath or outdoors. The key is fixed and the clockwork mechanism is sealed.
Speed boats became popular toys during the 1930s when various record breaking attempts were being made. Consequently model speed boats were often geared to attain high speeds at the expense of loss of distance covered. As a result of the use of the boats in ponds, pools or baths and the resultant knocks on cement edgings, older model boats in good condition are uncommon.