Now UI Kit - A beautiful Bootstrap 4 UI kit. Yours free.
Design Starter Kit for Sketch - A starting point for your next design project.
Dashboard UI Kit - A modern & responsive dashboard UI kit for designers.
Landing UI Kit - Handcrafted UI components for landing pages
Free Deca UI Kit - Clean UI Kit with necessary stuff to create design projects
Shards UI Kit - A free and modern UI kit based on Bootstrap 4.