OTA firmwares cannot be restored to. IPSW Downloads collects them for potential future use. They might also be useful if you're doing research.
| ✗ | Apple Watch Series 2 (38mm) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | bc867feca3970f8fca074e47f33d2b5335a2ac24.zip |
| ✗ | Apple Watch Series 2 (42mm) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | 738129b83b380d272990b8900e769f6c78eb2c6d.zip |
| ✗ | Apple Watch Series 1 (38mm) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | 85ab7fbc31a311bf3d1efcc95232e2aca377069e.zip |
| ✗ | Apple Watch Series 1 (42mm) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | 90ff3f7b5f5af74aa556a8f06b0bda1aca9d6d8f.zip |
| ✗ | Apple Watch Series 3 (38mm, LTE) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | 4bbade09c73b0cca7b6c039c5d989f273b73abc0.zip |
| ✗ | Apple Watch Series 3 (42mm, LTE) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | ae5a8bf38e530d3f787e6b5366f65945ade535e0.zip |
| ✗ | Apple Watch Series 3 (38mm) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | 9a3af9f186e1197c0c532e6ff5eb68ad0375e63b.zip |
| ✗ | Apple Watch Series 3 (42mm) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | 4f7ec4c45e6aa1513af937d5f28aa0ea73021426.zip |
| ✗ | Apple Watch Series 4 (44mm) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | f63c059e0ae2bbc563efaf2d40fda34639e9126f.zip |
| ✗ | Apple Watch Series 4 (40mm) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | 29fcf92ee6503a7a1999425ead6c2e32200c7709.zip |
| ✗ | Apple Watch Series 4 (40mm, LTE) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.4 GiB | 25e48dcb951e514ddeae61e58a733cffa7017a5b.zip |
| ✗ | Apple Watch Series 4 (44mm, LTE) | watchOS 5.3.7 (16U674) | May 18, 2020 | 1.3 GiB | 66f60cb8ec28648460c0a7a46179d280db9b8a44.zip |