The 68845NV basic set includes 16 carbons and 18 hydrogens which is sufficient to build any 2 basic amide structures.
Indigo Instruments has maintained a substantial inventory of genuine Cochranes of Oxford (Orbit) atoms & bonds for over 30 years. These parts are compatible with every student & teacher molecular model set we have sold since day 1. This level of quality may appear expensive but no parts support from other vendors costs even more.
Every Orbit molecular model set sold by Indigo Instruments is fully compatible with others you might own. You can replenish any set or customize it with Genuine Cochranes of Oxford Orbit Atoms.
I've had consistently great service from this company. Our students seem to really appreciate the reasonable price. In the years that we've used this product, not one has been returned due to defects.
Considering how many of these we sell to schools every year, that is high praise indeed. Thanks letting us know.