Side Pin Tooth (PENETRATION EXTENDED ) Part Number 1590559 Family J550 Standard Pin Part No. 6Y8558 Standard Retainer Part No. 8E5559 Heavy Duty Pin Part No. 1073378 Heavy Duty Retainer Part No. 1078559 Pocket Size 55=5.5in Machine: CATERPILLAR 988G, 992, 235, 245, 345, 350, 375 IF YOU CAN'T FIND WHAT YOU ARE LOOKING FOR, PLEASE CONTACT US. PRICE AND PART NUMBERS ARE USED FOR REFERENCE PURPOSES ONLY.