Side by side

Hamilton Khaki Aviation Converter Auto ChronovsSeiko Prospex SPEEDTIMER SPEEDTIMER Mechanical Chronograph Limited Edition

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

What people say

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Hamilton Khaki Aviation Converter Auto Chrono

The Hamilton Khaki Aviation Converter Auto Chrono is widely described as a large 44mm pilot's watch with a functional slide rule bezel. Reviewers note its well-finished steel case, featuring a robust satin-brushed finish with polished accents and chamfers, and a legible blue sunray dial with applied Super-LumiNova markers and old-fashioned hands. It is powered by the H-21-Si automatic chronograph movement, an upgraded ETA-based caliber with a silicon balance spring for anti-magnetic properties, offering a 60-hour power reserve. The watch is rated to 100m water resistance and features a bi-directional slide rule bezel with graduations printed under K1 mineral glass for scratch protection, which is easy to manipulate due to its deeply notched steel design. Some find the slide rule bezel complicated to use without a manual. One owner notes its character does not appeal as much as other slide bezel chronos.

Seiko Prospex SPEEDTIMER SPEEDTIMER Mechanical Chronograph Limited Edition

The Seiko Prospex SPEEDTIMER SPEEDTIMER Mechanical Chronograph Limited Edition is praised for its well-executed heritage inspiration, clean dial, and balanced design, with its in-house caliber 8R48 noted as a solid movement. Owners appreciate the Zaratsu polishing and the column wheel and vertical clutch on the 8R48 movement, considering it good value. Some find the date wheel deep-set and the bracelet lacking micro-adjustments. The 42.5mm x 15.1mm case size may be large for some wrists. On balance, owners and reviewers rate the Seiko Prospex SPEEDTIMER SPEEDTIMER Mechanical Chronograph Limited Edition highly for its heritage design and solid in-house movement.

At a glance

13 of 29 specs differ
Diameter
Khaki Aviation Converter Auto Chrono44mm
Prospex SPEEDTIMER SPEEDTIMER Mechanical Chronograph Limited Edition42.5mm
Power Reserve
Khaki Aviation Converter Auto Chrono60h
Prospex SPEEDTIMER SPEEDTIMER Mechanical Chronograph Limited Edition45h
Water Resistance
Khaki Aviation Converter Auto Chrono100m
Prospex SPEEDTIMER SPEEDTIMER Mechanical Chronograph Limited Edition100m
MSRP
Khaki Aviation Converter Auto Chrono$2,445
Prospex SPEEDTIMER SPEEDTIMER Mechanical Chronograph Limited Edition$3,000

Full specifications

Case

5 specs
Category
Pilot
Chronograph
Diameter
44mm
42.5mm
Thickness
14.6mm
15.1mm
Lug-to-Lug
0mm
50mm
Lug Width
22mm
20mm

Crystal & Dial

4 specs
Crystal Shape
Curved
AR Coating
Anti-reflective coating on inner surface
Dial Color
Black
Lume
None
LumiBrite on hands and index(es)

Movement

3 specs
Caliber
H-21-Si
8R46
Power Reserve
60h
45h
Jewels
0
34

Pricing

1 specs
MSRP
$2,445
$3,000
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