on-minifig-head is part of:

on-minifig-head contains:

Full expansion for on-minifig-head:
   100%  Aviator Cap w/ Black Goggles
   100%  Barbute Castle Helmet
   100%  Baseball Cap
   100%  Baseball Cap w/ Blue EMS Symbol
   100%  Bat-Lord Helmet
   100%  Bullet Castle Helmet
   100%  Bush Hat
   100%  Chef Hat
   100%  Construction Hat
   100%  Construction/Equestrian Hat
   100%  Cowboy Hat
   100%  Cowboy Hat w/ Silver Star
   100%  Cowl Hood
   100%  DragonMasters Helmet, no feathers
   100%  Firefighter Hat
   100%  Firefighter Hose-Helmet Bottom
   100%  Helmet w/ Clear Scuba Mask
   100%  Helmet w/ Flame Decor
   100%  Helmet w/ Red Line, Black "POLICE"
   100%  Helmet w/ Red/Green Stripes
   100%  Helmet w/ White Stars
   100%  Helmet w/ White Stars, Red Stripes
   100%  Imperial Guard Soldier Hat
   100%  Insectoids Helmet
   100%  Islander Hairpiece w/ Bones/Feathers
   100%  Jolly Roger Pirate Hat
   100%  King Kahuka Face Mask
   100%  King's Crown
   100%  Long Hair Piece
   100%  Male Minifig Hair Piece
   100%  Morion Helmet
   100%  Ninja Hood w/ Clip
   100%  Officer Cap w/ Brim
   100%  Pharoah Headdress Piece
   100%  Pigtail Hair Piece
   100%  Pirate Scarf/Bandana
   100%  Pith Helmet
   100%  Ponytail Hair Piece
   100%  Robin-Hood Hat
   100%  Samurai Helmet w/ Clip
   100%  Stingray Helmet/Apparatus
   100%  Stovepipe Top-Hat
   100%  Tri-Corner Pirate Hat
   100%  Vented Castle Helmet
   100%  Visorless 2-Stud Hose Helmet
   100%  Visorless Aquanaut Apparatus
   100%  Visorless Aquaraider Apparatus
   100%  Visorless Aquashark Apparatus
   100%  Visorless Hydronaut Apparatus
   100%  Visorless Space/Town Helmet
   100%  Visorless Spyrius Printed Helmet
   100%  Visorless Unitron Printed Helmet
   100%  Wizard/Witch Hat