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Walther P99 pistol (1st generation).
Walther P99 pistol (1st generation).

Walther P99 AS (Anti-Stress) pistol, 2nd generation.
Walther P99 AS (Anti-Stress) pistol, 2nd generation.

Walther P99 QA pistol.
Walther P99 QA pistol.

Walther P99 Compact DAO pistol, 2nd generation (note extended slide release lever, which is also duplicated on right side of the gun).
Walther P99 Compact DAO pistol, 2nd generation (note extended slide release lever, which is also duplicated on right side of the gun).
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Walther P88 Compact (note slide mounted safety instead of frame mounted decocker of the early P88).

Characteristics

Type: Double Action
Chamber: 9x19mm Luger/Parabellum
Weight unloaded: 900 g (822 g)
Length: 187 mm (181 mm)
Barrel length: 102 mm (97 mm)
Capacity: 15 rounds (14 rounds)