One enum for multiple models

At this moment I write enum in model concern:

  module Sizeable
extend ActiveSupport::Concern
included do
enum pizza_size: { d22: 22, d33: 33, d38: 38 }

Is there some more elegant way to do it with rails 4.1 standard enums? Before 4.1 I used EnumerateIt gem for this, but current standard rails enums is much cleaner.