Butcher BBQ er Pistol Grip Gourmet Meat Injector Metal Handle 50cc Pistol Grip Syringe with 2 Different Needles for Different Meats

The suction isn't working. I've tried pulling out the silver knob and tightening the dime sized knob all the way, but still nothing. Any thoughts? Thx

The syringe, is it plastic or glass?

Can a warranty be bought for this injector? That be nice so I can have it forever.

Is the metal of the pistol grip stainless steel?