<%= simple_form_for @physical_store, :url => api_physical_stores_path, :method => :post, remote: true, :wrapper => :bootstrap3_horizontal, html: { class: 'form-horizontal', accept: 'application/json', multipart: true } do |f| %>
  <%= f.input :day_from, :collection => DAYS_SF, default: 'Monday', required: true %>
  <%= f.input :day_to, :collection => DAYS_SF, default: 'Friday', required: true %>
  <%= f.input :time_from, required: true %>
  <%= f.input :time_to, required: true %>
<%= end %>

config.wrappers :bootstrap3_horizontal, tag: 'div', class: 'form-group', error_class: 'has-error',
              defaults: { input_html: { class: 'form-group default_class' } } do |b|

  b.use :html5
  b.use :min_max
  b.use :maxlength
  b.use :placeholder

  b.optional :pattern
  b.optional :readonly

  b.use :label, wrap_with: { tag: 'div', class: 'col-md-6' }

  b.wrapper tag: 'div', class: 'col-md-6' do |input_block|
    input_block.use :input
    input_block.use :hint,  wrap_with: { tag: 'span', class: 'help-block' }
    input_block.use :error, wrap_with: { tag: 'span', class: 'help-block has-error' }
  end
end

<div class="form-group string required physical_store_time_from">
 <div class="col-md-6"><label class="string required control-label" for="physical_store_time_from">Store Hours <abbr title="required">*</abbr></label></div>
 <div class="col-md-3"><input class="string required form-control" id="physical_store_time_from" name="physical_store[time_from]" type="text"></div>
 <div class="col-md-3"><input class="string required form-control" id="physical_store_time_to" name="physical_store[time_to]" type="text"></div>
</div>