Circle fiberglass mesh tape is used to prevent cracking at butt joints (where two sheets of drywall meet). It can be used on all butt joints and inside corners, followed by mud. This specific marking is self-adhesive, so there's no need to apply a layer of mud first; you can simply apply it directly to your drywall.

Self-adhesive drywall sealing tape significantly increases strength and durability to reduce cracks and gaps on the job site. No coating is required.