Modelcraft needle bearings modelcraft k 5x8x10 modelcraft s needle bearing 8mm od 5mm bore features a needle cage that provides a roller bearing with minimal radial construction space combined with great strength p needle bearings are used when the shaft and casing bore are designed as slide ways preferred application in model construction is to seat the ring gear on the engine crank shaft modelcraft k 5x8x10 needle bearing 8mm od 5mm bore