Ultralite Safety Set 3mm/60cm 10pcs.

These are good quality safeties. I like that they use screw-gate carabiners as they always feel more secure once in place. You do need to unscrew the gate completely to allow the other end to fit through it. I use a few permanently installed on my own lighting rig, but also like to keep some handy for when I rig temporary stuff for other people. Good for peace of mind, and also for compliance with insurance requirements!