Check the listing for details. Case For ZK-MT21 MT21 Power Amplifier Shell, 3d Printed. Condition: New. Listed at 13.00 USD. *This Listing does NOT include an amplifier* This is for a case ONLY This is for the case only, as this amp comes without a case and the electronics and motherboard are exposed on the sides and back. This was a custom design for a friend who worried about his kids sticking their fingers into it. This 3D printed case is the perfect addition to your Zk-mt21 amplifier. It is designed to fit your amplifier board and include the existing panels to adhere into fitted slots on the top and bottom. The shell will come with double-sided tape installed for the panels to be applied. Alternatively, a glue could be used for a more permanent application. The case is made from durable PETG and is built to last, ensuring that your amplifier stays safe and protected. These are printed in high quality and may have slight variations to the finish. This is expected with most 3d printed plastic. Assembly Instructions: You will need a screwdriver and small pliers to disassemble the amplifier. You will use some of the screws that came with your amp to secure the board inside the shell. The knobs of the amplifier will pull off and then the hardware Nuts can be removed with pliers and put back on after the board is popped into the case. Insert the knob posts thru their case holes and the fit of the amps front panel will be snug and may need to be pressed past the two front screw posts of the case. Use the screws you removed from your amplifier to secure the board inside the case. Then gently install the snap-fit lid onto the case.