Home » Products » Incremental Encoder » Hollow Shaft » HTR-HN HTR-HN Click on photo to enlarge Detailed product specifications, please open the PDF file from the attachment below Data Sheet SpecificationsFeatures Hollow Diameter: 8 mm. Pulse per Revolution: 10~2500 PPR. Hollow Shaft Encoder. Related Products HTR-HD HTR-HM HTR-HJ HTR-HB