I have a bayonet adapter plug for HK91 pattern rifles. It comes with all the necessary hardware to install, screw, lock washer and lock washer mounting plate. I’m not an expert, but I believe this is a German made part. I’ll do my best to answer any questions on it or send you additional pictures if you’d like. There are a few different bayonet and adapter styles and they are not all interchangeable so please look closely at the pictures and your bayonet if you already have one. I also have a few extra mounting plates that I ordered by mistake that I’ll include. I’m asking $70 shipped either PayPal FF or Venmo. Please PM me if you’re interested. I also have this listed on HKPro so sales will be based on time stamp if necessary. Thanks for looking.