This is a wonderful aid to help those with arthritis knit! The design features two gribs to hold the knitting needles as well as two holders of the needle gribs. The design can fit over top of a bowl to allow for the yarn and supplies to all stay in one place! 

This aid will cost approximately $1.48 for filament and another $5 for the velcro needed to attach the knitting needles to the gribs. The total cost is approximately $7.00. To my knowledge there is not a commercial version of this. Filament cost was $20 (https://www.amazon.com/AmazonBasics-Printer-Filament-1-75mm-Black/dp/B07D68S7BV/ref=sr_1_1?ie=UTF8&qid=1540474582&sr=8-1&keywords=amazon+basic+pla). The print utilzed 74 grams of filament.