1950s vintage Oster massager, Scientific electric massage vibrator with instruction booklet

Mid-century vintage Oster massager with original paperwork dated 1952. No box, and the booklet is showing some age - but the massage unit works fine. This is scary powerful, also very heavy! I believe this is the MI 'Scientific' model (that's what's marked on the machine), though it looks to me very much like an old Stim-u-lax.