Dynamic Dna Kit - 12 Base Pairs. The kits contain the following:2 Base Pairs Includes A-T and G-C base pair, 5' hydrogen and 3' oxygen parts, oxygen atoms to model RNA; removable carbons for uracil; ATP, TTP, GTP and CTP models; teacher resources and lessons.12 base Pairs Includes A-T and G-C base pairs; 5' hydrogen and 3' oxygen parts; oxygen atoms to model RNA; removable carbons for uracil; ATP, TTP, GTP and CTP models; display stand; teacher resources and lessons.