What is included: 1x Replacement Gear (Fits Sony Discman D-555, D-88, D-82, D-250, D-9, D-90, D-99, D-150, D-15, D-25) FAQ How is this gear made? This gear is 3D printed on a DLP resin printer. This means the final product is extremely high detail (see included magnified photos). What Sony Discman models does this work with Please see the models listed in the title. Does this include tracking? This item is shipped by USPS flatmail and does not include tracking. Tracking would increase the price by at least $3.80. Is this open source? Yes, I am the creator of this 3D design and have released it as open source so that other people can print these replacement gears for free. You can find the source files on thingiverse.com/thing:5718683 Does this listing include anything other than the one gear? No.