Bamboo and metal push-action pen with plastic trim.. Trim made with 45% biodegradable materials.. For best imprint results, we recommend PMS 877 or white ink on colored finish and PMS 469 ink on natural finish.. NOTE: Please note that bamboo is a natural fiber, therefore noticeable shade variations and grain patterns may be apparent within orders of the same item. Due to our high standards of quality control, we must advise that slight irregularities in the bamboo of this item may result in imprint imperfections but are consistent with the natural look of the product.