Parker · 1948–1969 · Aerometric
Aero-metric filler, 1948 to 1969
In 1948 Parker retired the Vacumatic filler from the 51 and switched to the Aero-metric, first sold as Foto-Fill. Unscrew the barrel and you'll find a see-through Pli-Glass sac inside a metal sleeve with a ribbed bar, and a few presses on the bar fill the pen. The outside barely changed. The barrel now ends without a blind cap, so there's only one jewel, and the Blue Diamond clip gave way to a plainer Arrow. By 1952 the sleeve was brushed stainless steel and asked for four presses instead of the six printed on the earliest ones. Parker sold the 51 until 1972, and estimates run from 20 to 50 million pens, so you can be choosy about colors like Forest Green, Midnight Blue, Cocoa and Burgundy. A U.S. pen from 1952 should still carry a date code. It's the easy-going 51 and the one we'd start with.
Parker expected about 30 years from the Pli-Glass sac and most are now well past that, so it's the part to test. Old dried ink in the hood can slow the flow until the pen is flushed, and caps get dented or swapped between pens.
Buying guide
For a pen you can ink up, our pick is the black 51 with a gold-filled cap titled working at $94 delivered, well under the band. There are 31 for sale and most ask $130–270 delivered, with Cocoa and Burgundy pens at $144–287 and restored ones near the top. Ask whether the Pli-Glass sac fills and holds ink, since Parker expected about 30 years from it and most are well past that, and read the date code by the clutch ring in the photos. Skip the $336 steel-capped pen with gold accents, which gives no reason for asking about $65 over the band.
$23.00est. delivered
The lowest current price on a complete 51 Aerometric, about $23 delivered with 7 bids and two days left at capture, so it will climb. We'd stop around $90 delivered, since a black 51 titled working asks $94.
Vintage Parker 51 Aerometric Fountain Pen – Brushed Steel Lustraloy Jeweled Cap
$93.99est. delivered
Titled working, with a gold-filled cap, for $94 delivered, well under the $130–270 band. Ask which nib grade it has and when it was last filled.
Parker 51 Aerometric Fountain Pen Black/Gold-filled cap working
$239.15est. delivered
Brownfoxpens titles this English-made Insignia as restored, so it should need the least work of any pen here. Ask what was replaced, and check the photos for initials on the signet, since engraving lowers the value.
PARKER 51 AEROMETRIC FOUNTAIN PEN INSIGNIA SIGNET ENGLAND -RESTORED (BFP717)
$162.34est. delivered
Cocoa is one of the 51 colors collectors look for, and this one asks $162 delivered, right in the middle of the band. The title doesn't say whether the sac holds ink, so ask.
VTG 5.375" Parker 51 COCOA Fountain Pen Aerometric filler
Delivered prices include shipping as eBay quoted it to a US address on Oct 5, 2026. Many sellers charge by distance, so your total may differ. eBay shows yours before you pay.
Snapshot
Checked . Some may have sold.
Delivered prices include shipping as eBay quoted it to a US address on Oct 5, 2026. Many sellers charge by distance, so your total may differ. eBay shows yours before you pay.
Used$23.00est. delivered
$17.50 + $5.50 shipping
Auction · 7 bids · ends in 2d 8h
Good buy
Auction with 7 bids at capture. It will climb.
Seller: pickeroftheyear
99.4% positive
Used$93.99est. delivered
$89.00 + $4.99 shipping
Buy It Now$89.00
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Good buy
Black with a gold-filled cap, titled working.
Seller: kraz
100% positive
Serviced$239.15est. delivered
$200.00 + $39.15 shipping
Buy It Now$200.00
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Good buy
English-made Insignia, titled restored. Shipping is $39.
Seller: brownfoxpens
100% positive
Used$162.34est. delivered
$155.00 + $7.34 shipping
Buy It Now$155.00
Good buy
Cocoa, one of the colors collectors look for. The sac isn't mentioned.
Seller: northernmichigan
100% positive
Used$24.49est. delivered
$15.50 + $8.99 shipping
Auction · 2 bids · ends in 4d 2h
Our take
Titled serviced, in black with a 14K medium nib. Auction with 2 bids.
Seller: writevinyl
99.7% positive
Used$85.70est. delivered
$75.00 + $10.70 shipping
Buy It Now$75.00
Our take
Blue barrel, chrome cap, fine nib. No word on the sac.
Seller: allthisjunk4u
99.8% positive
Used$356.17est. delivered
$350.00 + $6.17 shipping
Buy It Now$350.00
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Our take
Demonstrator with a clear shell, titled 1948 and working. Rare, and priced for it.
Seller: frenchie1326
100% positive
Used$335.82est. delivered
$330.00 + $5.82 shipping
Buy It Now$330.00
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Priced high
About $65 over the band, with no reason given in the title.
Seller: arnoldlam
100% positive
Prices change daily. The live eBay search shows everything listed now, including anything new since Oct 5, 2026.
See every listing on eBay ↗eBay searchA pen that’s sat in a drawer for decades wants a flush before it sees ink. A bulb syringe, pen flush and a bottle of well-behaved ink cover most of it. This searches Amazon for the usual kit.
Search pen care kits ↗Amazon search
Parker · 1948–1965
AerometricMark I, 1948 to 1951
Post-war golden age
$25–$40 typical ask
Parker · 1948–1960
AerometricShorter 51, 1948 to 1960
Post-war golden age
$100–$190 typical ask
Parker · 1941–1948
VacumaticVacumatic filler, 1941 to 1948
Pre-war and wartime
$100–$210 typical ask
Parker · 1937–1948
VacumaticMid-size Vacumatic, 1937 to 1948
Pre-war and wartime
$140–$240 typical ask
Parker · 1921–1936
Button and lever fillerPermanite flat-top, late 1920s
Pre-war and wartime
$270–$490 typical ask
Parker · 1964–1994
Cartridge and converterSterling silver crosshatch, 1964 to 1994
Post-war golden age
$140–$210 typical ask