---
title: GB Series Flex-Hone Tools | Cylinder Hones | BRM
description: "GB Series Flex-Hone® tools are flexible cylinder hones for bores with diameters from 3-1/4\" (83mm) to 4-5/8\" (118mm)."
image: https://info.brushresearch.com/hubfs/BRM_GB31212.jpg
---

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## Standard-Duty Cylinder Hones for Medium Dia. Bores 3-1/4" to 4-5/8" 

### **GB Series Flex-Hone**®** Tools**

GB Series Flex-Hone® tools are flexible cylinder hones for bores with diameters from 3-1/4" (83mm) to 4-5/8" (118mm). These surface finishing and deburring tools are described as "standard-duty" because they have a shorter abrasive length than [GBD Series Flex-Hone® tools](https://info.brushresearch.com/gbd-series-flex-hone-tools), which provide more abrasive per hone and typically last longer.

GB Series Flex-Hone® tools have an overall length of 13-1/2" (342.9mm) and are available for five bore sizes: 3-1/4" (83mm), 3-1/2" (89mm), 3-3/4" (95mm), 4-1/8" (105mm), and 4-5/8" (118mm). To provide a soft cutting action, flexible cylinder hones are supplied and used in an oversized condition. For example, the GB Flex-Hone® for a 3-1/4" bore has a tool diameter that's slightly larger than 3-1/4". 

Like other medium-diameter Flex-Hone® tools, GB cylinder hones are available in seven standard abrasive types, and in grit sizes that range from 20 (coarse) to 800 (fine). As a rule, start with a coarser-grit Flex-Hone® and then use a finer-grit tool. Always use a high-quality lubricant such as Flex-Hone® oil and lubricate the tool generously.

Automotive applications for GB Series Flex-Hone® tools include deglazing and finishing engine cylinders and cylinder liners. Industrial applications include any cylinder that requires deburring or surface finishing within the appropriate size range. GB Series Flex-Hone® tools are designed for use with most any rotating spindle. Examples include handheld electric drills and CNC machining centers.

[Order GB Series Flex-Hone tools](https://www.brushresearch.com/collections/flex-hone%C2%AE-tools?filter.p.m.custom.series=FLEX-HONE%C2%AE+GB+Standard+Duty+%283-1%2F4%22-4-5%2F8%22%29)on-line or complete the form on this page to download the BRM Catalog.<http://www.brushresearch.com/brushes.php?c1=2>

![GB_GBD_Flexhone](https://info.brushresearch.com/hs-fs/hubfs/Email_Template_Images/Automotive_Product_Images/GB_GBD_Flexhone.png?width=600&height=443&name=GB_GBD_Flexhone.png)

 

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