This kit is built using only 2 piece types, a male and female connector that snap in along the center of the helix. This kit can be pressed flat or spun into a helix. This allows it to represent a DNA double helix and an RNA single helix during replication.
A comparable DNA kit is linked below. However it does not have a customizable length, and costs $70. For comparison, printing my kit cost about 50 cents in PLA.