Timing belt Optibelt 6 AT3 / 639

OPTIBELT 6 AT3 / 639 belongs to timing belt, part of our Power transmission range. Tell us how many you need by WhatsApp or email and we'll get back to you promptly with a quote for 6 AT3 / 639 and any equivalents.

The Optibelt Alpha Torque 6 AT3 / 639 is a timing belt with an AT3 profile. It measures 639 mm in length and has a 3 mm pitch. This page covers what to look for when reading the marking on the old belt.

The marking on the back of a timing belt is the most direct way to identify the replacement. On this Optibelt Alpha Torque belt, the marking shows 6 AT3 / 639. The 639 indicates the length in millimeters, and AT3 identifies the profile. The pitch is 3 mm. Read the full string from the old belt before you order, including any numbers that come before or after it.

If the old belt is worn, dirty or cut, the marking may be hard to read. Wipe it with a clean cloth and check the full length of the back. Do not rely on a partial number or on a belt that looks similar. A belt with the same profile but a different length will not fit the drive correctly. Write down the complete marking, then send it to us.

Once you have the marking, send the part number, 6 AT3 / 639, by WhatsApp or email to request a quote. If you are unsure whether the marking matches your drive, include a photo of the old belt and the drive. We carry the Optibelt Alpha Torque line and can confirm the belt or suggest an equivalent.