Seiko 6138-7000 slide-rule chronograph from July 1974. I’ve owned this watch for many years. The original restoration was a collaboration between myself, Jonathan Koch, and Lew Brown. It is a wearable worry-free example of this super cool and not that common pilot’s chronograph, with a slide-rule to allow quick conversions and other feats of mathematical genius.

• 6138b movement is fully serviced

• Case is clean with no corrosion or pitting; all the sealing surfaces are great.

• Original dial

• Original hands

• All lume is original

• Slide-rule insert and rotating ring were NOS when installed, and are in great shape.

• chronograph hands had faded to white; I re-tinted them back to the correct orange, and the paint I use doesn’t fade in the sun like the original color.

• Spanish/English daywheel

• Handwinding

• Automatic winding

• All functions function

• Bracelet is the excellent modern reproduction - solid stainless steel and in great shape. I added a genuine Seiko clasp.

• No returns