For a single instance of a class, you can simply
<b id='edit-open-hours'>Open Hours</b> <%= best_in_place @provider, :open_hours, type: :select, collection: Provider::PROVIDERS_HOURS, activator: '#edit-open-hours' %>
If you want to do this with a list, you will need to make each id unique with an id
<b id='edit-<%= @provider.id %>'>Open Hours</b> <%= best_in_place @provider, :open_hours, type: :select, collection: Provider::PROVIDERS_HOURS, activator: '#edit-' + @provider.id.to_s %>
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