Genuine arm included! I have added pictures, please take a look. This is a Carparelli Guitars PRS-Style Tremolo Bridge Brass Bloc Stratocaster tremolo bridge. Operation has been confirmed. It has been used for a short period and is in good condition. Included items: Tremolo unit, mounting screws (with grooves), 3 springs, and spring hanger set. Shipping is free. Please refrain from bidding if you are concerned about scratches, stains, or dullness, as this is a used item. I am a smoker and live with pets, but storage and testing are done in a non-smoking room where entry is prohibited. I don't think there is any odor, but please refrain from bidding if you are concerned.