Mask
The most important piece — your view underwater. A good mask seals and keeps water out.
A full-face mask (easier for beginners) or a comfortable eye mask with a soft silicone strap.
A single-lens low-volume mask is clearer and lighter.
A small freediving mask — easier to equalise.
Test the mask by holding it on your face without the strap — if it stays with a sniff, it fits.