https://www.titleist.com/teamtitleist/team-titleist/f/golf-clubs/16856/iron-serial-numbersI own two sets of Titleist MB irons. My 690 MB irons have the serial number on the 6 iron. However my other set (bought in 2001) has no serial numbers on any of the clubs. The set is the limited edition/production of the Tiger Woods irons (681 MB). Iten-USTelligent Community 10https://www.titleist.com/teamtitleist/thread/293807?ContentTypeID=1Mon, 12 Jul 2021 17:24:06 GMT9ab519fc-5311-4952-85cd-0a0ceffb73fb:c8cf7979-3349-4b80-85a6-b996e0f0191dRyan LHi Peter!<br /> I know this is a late reply and perhaps you’ve gotten more details already.<br /> From my understanding, serial numbers are only added for specifications applied to an order that is outside standard. As an example, i ordered a set of AP1’s for my son a few years ago after a fitting and no serial numbers appear because they are bone stock. Standard length, loft and lie, with stock shafts and grip.<br /> Any deviation, say 1/2 long, would have then come with serialization.<br /> Not sure if that helps or makes sense but wanted to share if helpful.<br /> All the best!<br /> RL<div style="clear:both;"></div>https://www.titleist.com/teamtitleist/thread/286242?ContentTypeID=1Thu, 04 Feb 2021 21:38:03 GMT9ab519fc-5311-4952-85cd-0a0ceffb73fb:01ffb806-9f01-4db4-b7dc-e1e450f0ee11Peter OOK, this is a very old thread but I’m going to post anyway….<br /><br /> I recently purchased a full 2-PW set of pre-owned 681 irons. This set has TT DG S300 Sensicore shafts – the 2 iron has never been regripped and has the original Titleist full cord setup. On-line information about 681 sets is all over the place. Every thread I’ve investigated seems to say something a bit different.<br /> Some irons have serial numbers on the hosels, some don’t, some only on the 6 iron. No one knows what the serial # means. Some sets are custom grind some are stock. I get that the markings are very different. I called Titleist to ask if they could help with my set and got no results. <br /><br /> I’m assuming my set is stock and came with Sensicore shafts – 2 iron has never been regripped.<br /> Was this a stock set up?<br /> My set has serial numbers on back of each hosel - 219LB<br /> Does the SN tell us anything?<br /><br /> This is a chat on the Titleist site….Can a technician help solve the mystery of the Serial #?<br /><br /> We all agree these are amazing clubs. We’d all like to learn a bit more about the genesis of our sets. 20 years ago is not ancient times.<br /><br /> If anyone can help, thanks!<br /><div style="clear:both;"></div>https://www.titleist.com/teamtitleist/thread/75946?ContentTypeID=1Tue, 15 May 2012 19:44:01 GMT9ab519fc-5311-4952-85cd-0a0ceffb73fb:2c166620-4991-4cba-bff5-4de631fe7c8dlaurent p<p>All titleist sounds to have serial on N6 hosel, whatever i have a 681 wich have number on all hosel ?</p> <p>i realy dont know what it stand for ? </p><div style="clear:both;"></div>