Choosing the Right Envelope Sealer: A Buyer’s Guide to the All For Mailers Lineup, from the AFM60S to the Formax FD 432

Envelope sealing is one of those mailroom tasks that’s easy to overlook until volume outpaces what a person can seal by hand. All For Mailers carries a lineup of envelope sealers built for a range of volumes — from an entry-level machine for occasional runs up to a single-pass production unit rated at up to 18,000 envelopes per hour. Here’s how the lineup breaks down, plus a practical detail that determines how many envelopes per hour you’ll actually seal once you own one.

Starting Out: The AFM60S

The refurbished AFM60S Low-Cost Envelope Sealer ($1,295) is the entry point of the line. It’s named for its rated speed — 60 #10 envelopes per minute — making it a fit for lower-volume mailings that still need to move faster than sealing by hand allows.

Stepping Up: The AFM80S

When volume grows past what the AFM60S comfortably handles, the refurbished AFM80S Envelope Sealer ($1,695) is the next step up. Same naming logic applies — it’s rated for 80 #10 envelopes per minute — giving you more throughput without moving into full production equipment.

The Production Step Up: RENA ES-450 and EFS Pro

For genuinely high-volume mailing, the next rung up is a different class of machine, rated at up to 10,000–12,000 envelopes per hour depending on envelope size and sealing fluid. It’s sold under two names — the RENA ES-450 Envelope Sealer and the Postmatic EFS Pro Envelope Sealer — and they’re the same machine.

Here’s the story behind that. The EFS Pro is marketed by Postmatic, who holds the distribution rights to it, at a $7,500 MSRP. At one point, Quadient/RENA rebadged a run of these units to sell as the RENA ES-450, originally listed at $11,840, then stepped away from the line. All For Mailers bought the remaining four RENA-badged units outright and now holds the last three units anywhere ever labeled RENA ES-450 — priced at $5,495.

Both versions handle envelopes from A5 (5-3/4in x 4-3/8in) up to 10in x 13in, with product thickness from 0.003in up to 0.25in, and both come with the same practical consideration below.

The Top Rung: Formax FD 432

At the top of the lineup sits the Formax FD 432 Envelope Sealer ($10,695), a single-pass machine that closes AND seals envelopes at speeds up to 18,000 per hour. Where the ES-450 and EFS Pro seal open-flap envelopes, the FD 432’s flap closing bar accepts standard stacked or nested envelopes with flaps open and does the whole job in one pass. It also handles bigger, thicker work — up to 13in x 15in and up to 15mm thick — so everything from standard #10s to stuffed booklet envelopes runs through it. For lettershops and mailrooms running true production volume day in and day out, this is the machine.

Installation and operator training are available on any sealer in this lineup. It’s quoted separately, per machine and location, rather than bundled into the listed price — worth asking about if you’re setting up a new mailroom rather than replacing an existing sealer.

The Part Most Buyers Miss: Sealing Fluid Quality

Here’s the detail that actually determines how many envelopes per hour you’ll seal in practice, and it has nothing to do with the sealer itself.

A sealer’s belt can physically move envelopes far faster than its rated sealing speed. Do the math on a 300 ft/min belt and you get roughly 35,000 envelopes an hour at #10 width with a 2-inch gap, or around 18,700 an hour running long-edge. Those are theoretical feed rates, not sealing throughput — the belt isn’t the bottleneck. The fluid is.

The moistening system can only wet each flap as fast as the fluid allows. That’s why the ES-450 and EFS Pro are rated at 10,000–12,000 envelopes an hour rather than closer to belt speed — and it’s also why sealing fluid quality matters more than most buyers expect. It’s the reason sealing fluid exists at all rather than plain water: quality fluid activates envelope glue faster and helps prevent mold, bacteria, and rust from building up in the reservoir and moistening system between runs. Real-world throughput on any of these sealers depends on fluid quality as much as belt speed.

SuppliesForMailers.com carries the sealing fluid All For Mailers recommends — in pre-mixed, liquid concentrate, and powder concentrate formats from 1 gallon to 55 gallons — and it’s worth pairing with any sealer in this lineup, not just the high-volume units. Parts for the EFS Pro and ES-450 are also available through SuppliesForMailers.

Protecting the Investment

All For Mailers offers a 1-Year Express Exchange Warranty for Envelope Sealers ($200), which covers the AFM60S and AFM80S — if your covered sealer ever needs service, an exchange unit ships fast so you keep sealing while the repair is handled. The Formax FD 432 comes with its own package: a 180-day defect warranty, 10% off an extended warranty, and an $860 SuppliesForMailers.com gift certificate. For the ES-450 and EFS Pro, call 866-430-2874 to talk through coverage options.

Matching the Machine to the Mailroom

In short: the AFM60S for occasional, lower-volume sealing; the AFM80S once volume grows past a couple thousand envelopes at a stretch; the RENA ES-450 or EFS Pro when you’re running production volume at 10,000+ envelopes an hour; and the Formax FD 432 when you need flap closing and sealing in one pass at up to 18,000 an hour. Whichever machine fits, pair it with quality sealing fluid — it’s the difference between a sealer’s rated speed and what you actually get out of it day to day.