Pillow Block Linear Ball Bearing IPPS24G 1.50" Closed - Self Aligning Precision PlusClosed Linear Ball Bearing Pillow Block with a 1. 5" ID (inner diameter) crowned shell self aligning bearing inside a housing made of aluminum alloy. The IPPS products all come with a grease zerk fitting, a small hole in the pillow block which is also called a lubrication port. Temperature Range: 4 +176F ( 20 +80C) Variant ID Sizes: Available from 1 4" to 2 Inch Series, 8mm to 50mm Metric Interchangeable: Size interchangeable with industry standards