Specific collagens and insoluble proteins called cuticlins are major constituents of the nematode cuticles. The epicuticle. which forms the outermost electron-dense layer of the cuticle. is composed of another category of insoluble proteins called epicuticlins. https://www.bekindtopets.com/limited-value-Rx-KBroVet-CA1-potassium-bromide-Chewable-Tablets-for-Dogs-500mg-60-ct-save-more/