A geometric sans much like Futura, but with joining strokes. Issued by Photo-Lettering as Thomac in four numbered weights (2, 4, 7, 10) [PLINC One Liner 1971].

Nick Curtis credits the design to George Piscitelle [MyFonts].* His Kallilu NF explores a similar concept, albeit with different base glyphs.
*) This info isn’t found in Photo-Lettering’s One Line Manual or the Alphabet Thesaurus Vol. 3.