Longines Caliber L688.2

The Longines caliber 688.2 is a tri-compax (3-6-9 layout) automatic column wheel chronograph watch movement found in dozens of Longines timepieces.

Interestingly, there is no mention of the L688.2 in the current Longines catalog, only L688 and L688.4. For example, searching the official Longines instruction manual database for L688.2 automatically pops up with L688.4 as a suggestion. Just typing “L688” lets you search for L688.

Editor’s Comment: Be forewarned that as per usual with Swatch brands/ETA modern caliber numbers, there is a lot of confusion around the L688 family of movements: which models have what, which calibers are based on what, which base calibers feature what. Much of this comes down the brand’s lack of caseback or movement imagery, lack of press-release information, etc. Presumably, confusion like this is the intention, as much of the watch industry has still not figured out that consumers want to know what they are buying and the smoke and mirrors and limited transparency is not desired.

Base Caliber:

When the L688.2 was announced at Baselworld 2009, it was based on the ETA Valgranges caliber A08.231. In 2010, the base caliber number apparently changed to the current A08.L01. This is why you may find older articles and press-releases stating that the L688.2 is an A08.231. This was also around the time ETA started ramping up their plans to stop selling movements outside of the Swatch Group, so most of the A08 calibers are not easy to find technical information about.

Editor’s Comment: Of course, you know what I’ll say… if they changed the base ETA caliber then they should have updated the main Longines caliber number as well to avoid any Caliber Confusion.

Currently, the L688.2 is essentially an ETA Valgranges caliber A08.L01. In fact, while the rotor is signed Longines and “L 688.2”, the caliber number under the balance wheel is “A08L01”. The A08.L01 is considered to be an ETA 7753 (7750) with a column wheel chronograph system.

If you have a watch with a rotor signed L688.2 and A08231 under the balance wheel, please post it in the comments…

L688.2 Vs L688.4:

There is a similar caliber L688.4 with the main difference being that the .4 designation is a COSC spec chronometer with an anti-magnetic silicon hairpsring (Si 14) and the .2 does not have certification nor a silicon balance spring.

Power Reserve:

When it was introduced, the L688.2 was said to offer 54 hours of run time. As of 2023, Longines information states that watches with their “L688” and L688.4 are capable of up to ~66 hours of power reserve (this number is provided officially by Longines (source), although it’s common to see other watch publications state anything from 60, 64 or 65).

How many turns of the crown to start the watch?
According to Longines, you should manually wind your watch about 30 times from a stopped state.

Setting the Time/Date:

• Do not attempt to set the time/date when the chronograph is running.
• Do not set the date when the hands are between the hours of 8pm and 3am.

To set the time, pull the crown out one click to time setting position. This will stop aka “hack” the small running seconds hand (subdial at 9:00). You can turn the crown in either direction to set the time.When the desired time is reached, press the crown back in (screw-in if needed).

Note: Most watches with a date complication have two crown positions (therefore 2 clicks), but the L688.2 date is not set via the crown – it is set via a pusher on the side of the case at 10:00 (similar to the ETA 7753 this movement is based on).

Replacement Prices:

There is of course no official replacement pricing for the calibre L688.2, since it is not available for indivual or wholesale purchase. The only way to obtain a complete movement would be to pull one from a parts watch, or be a Longines AD or certified technician and order a replacement from Swatch Group. However, interestingly, there was a raw movement for sale on eBay at the time this post was written – with an asking price of $1,150 USD or best offer. The packaging is interesting to see…

Video User Guide:

Additional Resources:

• Official instruction manual (pdf)
• More Longines watch movements