ITEM NAME:10pcs HCS Deep V Groove Sealed Guide Line Track Pulley Ball Bearing 4*13*6mm FT Features: Wire pulley grooveï ¼Å’Wide application This item is ordinary precision, adaptation to low speed, low load applications Specifications: Material:High carbon steel Dimension:(Inside diameter)4mm x (outer diameter)13mm x (thickness)6mm V groove width: 4.8mm.Wire pulley grooveï ¼Å’Wide application. 10 pcs Wire pulley with V groove. This item is ordinary precision, adaptation to low speed, low load applications. V groove width: 4.8mm. V groove deepness: 1.8mm.