This headrest hook is flexible and will bed to provide a lovely snug fit over most seat backs. 

Its reversible so safer for rear seat passengers. 

I find that when mounted hook in, my coats sit closer to the seat adn stay out of the way better. 

I have two plates one in ASA for best strenght, head and UV resistance and one in PLA for everyday 

It should scale easily for wider headrest uprights but this fits Landrover, jaguar, mini, and VW headrests. 

The ASA has a fairly high shrinkage rate so the design should be tolerant of high shrinkage filament ( silks etc)  but beware these can take a little freeing off.