JDB 4 is based on cast irom Ht250 and embedded with solid lubricant.Very good performance when under low load. Not suitable for middle and high load. A typical cost saving material, can substitute JDB-2 to be applied in the position without high requirements such as die guider, plastic injection machines etc. Base material:HT-250 Base Hardness:HB180-230 Friction coef(u):<0.18 Temperature limit :400 Dynamic load limit:60N/mm2 lLoad limit under lm/min:15N/mm2 Speed limit:0.5m/s PV limit:0.8N/mm2 *m/s Contact:www.cblbearing.com cblbearing@gmail.com