Martin Yale PostMark 3056

Speed: 8,000 envelopes per hour (production); 24,000 per hour (theoretical) · Maximum thickness: .25" (6 mm) auto feed; .39" (10 mm) manual feed

Current

Listed on the manufacturer's website (source, as of Oct 18, 2026)

Martin Yale PostMark 3056 — Image: Martin Yale

Speed8,000 envelopes per hour (production); 24,000 per hour (theoretical)

Maximum thickness.25" (6 mm) auto feed; .39" (10 mm) manual feed

Cutting methodMilling cutter; depth of cut 0.7 mm (factory set), 0-3 mm (tool adjust)

Envelope sizesn/a

Where to buy

Authorized dealersListed by the manufacturerFind a dealer · Maker's site

Machines in this class are mostly sold and serviced through the manufacturer's authorized dealers. We didn't find an Amazon listing for this exact model with a current offer. We don't show prices; ask a dealer or check the retailer for the current price.

Specifications

Brand	Martin Yale
Model	PostMark 3056
Type	Automatic letter opener (milling cutter)
Cutting method	Milling cutter; depth of cut 0.7 mm (factory set), 0-3 mm (tool adjust)
Speed	8,000 envelopes per hour (production); 24,000 per hour (theoretical)
Daily volume	Up to 20,000 filled envelopes
Feed	Hopper capacity 300; feeder capacity 100 envelopes; mixed-thickness separator
Maximum envelope length	13" (330 mm)
Maximum thickness	.25" (6 mm) auto feed; .39" (10 mm) manual feed

PostMark is Martin Yale Industries' letter-opener and addressing brand ("Postmark by Martin Yale Industries").

Values as published by the manufacturer, in its own units. Fields the manufacturer doesn't state are left out rather than estimated. Shown without scores or rankings.