Barwalt 3/16" T Hollow Leave-In Tile Spacers are industry-approved, hollow-core spacers designed to remain in the grout joint, eliminating the need for removal. This innovative design allows installers to grout a day earlier, saving time and streamlining the tiling process. The spacers mimic the flexibility of rubber spacers but feature a hollow center that allows grout to flow through, integrating the spacer into the joint for a seamless finish.