About this item Eartip has a bore size of 4.5 mm, which fits earphones with a sound port nozzle of 5-6 mm (mostly with BA drivers). Comparable to T-500. Compatible with various models and included in the box for select earphones. Package includes 2 pairs of silicone replacement eartips (4 pieces). Size: 6 x 2.1 x 0.7 inches.