This section is limited to published Action & 360 cameras models and tasks. Use model-specific evidence before buying a replacement part or accessory. Similar product names do not guarantee a match.
Insta360 X2 has Type-C USB 2.0; that connector specification does not establish every accessory pairing. X2 supports the Insta360 Mic Adapter (Vertical Version), not the X3 Mic Adapter. It also supports the X2 Fast Charge Hub and X2 Lens Cap; those exact names matter when replacing older kit.
Insta360 X3 has Type-C USB 2.0; that connector specification does not establish every accessory pairing. X3 supports the X3 Quick Reader and X3 Fast Charge Hub. The X4 Quick Reader and X4 Fast Charge Hub are not supported, even though some simpler X-series accessories are shared.
Insta360 X4 Air has Type-C USB 3.0; that connector specification does not establish every accessory pairing. X4 Air supports the X5 / X4 Air Quick Reader and Mic Adapter, but not the X5/X4 Lens Cap. A shared reader family is not proof that a cap or charging case will also fit.
Insta360 X4 has Type-C USB 3.0; that connector specification does not establish every accessory pairing. X4 supports its X4 Quick Reader, not the X5 / X4 Air Quick Reader. It does support the shared X5/X4 Lens Cap, so the reader result should not be extended to every newer accessory.
Insta360 X5 has Type-C USB 3.0; that connector specification does not establish every accessory pairing. X5 accepts the X5 / X4 Air Quick Reader, but not the X4 or X3 Quick Reader. Some shared accessories fit while model-shaped parts do not, so check the named item instead of assuming an entire older kit carries over.