Unit large atoms can be configured with any standard VSEPR geometry by means of 3 different "bond pegs" as shown in the image. Unit atoms come in two halves, so "equator" refers to the space between them that can accept the radial peg.
The radial peg on the left will create a univalent atom when only 1 is used. A 180o linear atom uses 2 at opposite sides of the "equator". A trigonal has 3 & are placed 60 degrees apart in the "equator". They can also be combined with the other pegs in non-equatorial holes for any geometry.
The polar peg shown in the middle can be used on one end to create a univalent atom or one at each end for a 180o linear shape. Use polar pegs & 3 radial pegs to create a trigonal bipyramidal atom.
The 4/8 peg on the right is used to construct the tetrahedral (sp3) atoms or 8 coordinate atoms for metals.
Each package contains: 72 pieces: (36 tetra; 24 radial;12 polar)