IPSW Portal

Choose aProduct→Choose aPlatform→Choose aVersion→ClickDownload

Download 5.1 (16R5589c) for Apple Watch Series 4 (44mm, LTE)

Version:	5.1
Build:	16R5589c
Signed:	No
Size:	0.12 GB
Release Date:	2018-10-22 17:20:06
Upload Date:	2018-10-19 17:03:10

Secure download directly from Apple's servers