Hamilton Khaki Field Auto vs Seiko 5 Sports Field SRPG35

Both are field watches. In short: the Hamilton Khaki Field Auto has a sapphire crystal — more scratch-resistant for daily wear. The Hamilton Khaki Field Auto is automatic, 100m water resistance, 42mm, sapphire crystal; the Seiko 5 Sports Field SRPG35 is automatic, 100m water resistance, 39.4mm, hardlex crystal.

Last verified 2026-06-27 · specs from manufacturer data · tier = price band, confirm the live price at the retailer

Spec	Hamilton Khaki Field Auto	Seiko 5 Sports Field SRPG35
Movement	Automatic	Automatic
Water resistance	100m	100m
Case size	42mm	39.4mm
Crystal	sapphire	hardlex
Style	Field / explorer	Field / explorer
Price tier	Upper	Mid

Which should you buy?

The Hamilton Khaki Field Auto has a sapphire crystal — more scratch-resistant for daily wear
The Hamilton Khaki Field Auto wears 42mm vs the Seiko 5 Sports Field SRPG35's 39.4mm — choose by wrist size
The Seiko 5 Sports Field SRPG35 sits in the lower price tier (Mid) if budget leads

Where to buy

Hamilton Khaki Field AutoSee price on AmazonCheck price

Seiko 5 Sports Field SRPG35See price on AmazonCheck price

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FAQ

What's the difference between the Hamilton Khaki Field Auto and the Seiko 5 Sports Field SRPG35?
Both are field watches. The Hamilton Khaki Field Auto is automatic, 100m water resistance, 42mm, sapphire crystal; the Seiko 5 Sports Field SRPG35 is automatic, 100m water resistance, 39.4mm, hardlex crystal.

Which is better value, the Hamilton Khaki Field Auto or the Seiko 5 Sports Field SRPG35?
The Seiko 5 Sports Field SRPG35 is the lower-priced tier; the other steps up in build for more money — confirm both live prices at the retailer.

Citing these specs? Go ahead — manufacturer data, last verified 2026-06-27. Copy a ready-made reference:

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