Emsis

Thank you!

Hi there (hooray, my first post) I found this little guy here, I remember I already had it in my childhood (~30 years ago). Could somebody tell me what LEGO family it is? The grid size is 2x2 LEGO studs, it just fits right onto one Duplo stud. On the inside I see the LEGO logo and the following indication "4 01". Greetings!