Masi Bits - “Spoon” Lugs 

This is the “Spoon” lower head lug that appeared on the first 350 (approximate) Carlsbad frames.

On later frames, the lower part of the lug was refined, giving it a sleeker look, in my opinion.  But collectors still prize the early examples.

This is the underside of the refined lug pattern (though this is a later investment-cast example).