The package contains two pedals, two beaters, a crossbar, a pair of patches, and a drum key. No instruction in the box. Our double bass drum pedal is easy to assemble. It’s smooth and fast, good for beginners and practicing. Adjustable for wits spring tension and beater & pedal heights. The beater is double-sided. Felt on one side and hard plastic on the other. We provide a drum key that makes the minor assembly simple and easy to adjust. Install step: – STEP1: Attach the crossbar to both pedals. STEP2: Tighten the screws. STEP3: Get adjusted to your setup and feel. STEP4: Before playing, check all the screws & bolts. Make sure all the screws and connectors were tight. STEP5: Install the bass drum double pedal patch on your drum. If you aren’t sure you’ll like it, you can use some scotch tape to mount it temporarily if you want a trial run. When the patch wears out you peel it off. The adhesive may leave a mark, you can use some rubbing alcohol to remove the old glue when replacing it. The drum patch can help your attack and make your batter side head last longer.