These signs are the universal representation for a stop sign. They are used in schools for pupils with special needs to indicate something that is not allowed. It is suggested, for example, that if a pupil fiddles with sockets/switches, this sign is printed, the white part in the middle cut out, laminated and placed over the socket/switch to indicate to the pupil that it is not to be touched. It can have lots of other uses. There are two of these signs on an A4 page in this resource.
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