Do you know the purpose of this spring mattress

Do you know the purpose of this spring mattress? Do you know the purpose of this spring mattress? Do you know the purpose of this spring mattress? Do you know the purpose of this spring mattress? Do you know the purpose of this spring mattress? Do you know the purpose of this spring mattress? Do you know the purpose of this spring mattress? Do you know the purpose of this spring mattress? Do you know the purpose of this spring mattress