These are aftermarket poppet/stems made out of Delrin, which is better for high pressure air. Made in Canada. The Chief 2 has a 2 mm shorter stem on it.
The stem length on these is:
QB Chief updated version 33.5mm
QB Chief Early Version 35mm
QB Chief 2 31mm
QB78/79/AR2078/79 37.5mm
Sorry. For my late review. Order the valve stem for my dead (almost two year not working because of valve stem could find it) Beeman QB Chief now she is alive again ( shooting ). Thank you ,and Thank you. Without you my Beeman QB Chief Would be still resting in peace. Have buy from you and will continue to do so. 5*****
Do you have a replacement for the Beeman qb Chief,if not can you make it
yep you should see the option on the product page. Thanks,