The shop is closed until Thursday, March 22. All orders received during our absence will be shipped promptly upon our return.

Please make certain that the part you are ordering is the one you need -- returns of parts will not be accepted unless defective or not as described.

Sacs and seals are fresh production. Prices listed below do not include shipping or insurance. If you wish to buy more than one of an item, quantities can be adjusted within the shopping cart before checkout.

Tools & Accessories -- Pencil Lead -- Nibs -- Other Parts

These traditional latex rubber sacs are all fresh production from the Pen Sac Company (the inheritors of the old White Rubber Company's ink sac operation). A sac of size "n" will slide freely into a hole n/64ths of an inch in diameter. Unless otherwise noted, all sacs are straight (i.e., not necked or tapered). Sacs are sold by the bag, $12 for five sacs, or an assortment of twelve in the most useful sizes (our choice) for $24.
NOTE: While latex rubber sacs can last for years under normal conditions, the use of certain inks can lead to rapid failure. Read more about ink selection for vintage pens here, and about sac materials and installation here.

Sac size Quantity (bags)
16 tapered
17½ x 2⅛ necked
21 x 3¼ necked
23 x 3⅛ necked
24 x 3¼ necked

100% silicone sacs will outlast conventional latex sacs several times over, and are unaffected by the most reactive inks. As far as we know, these are the only genuine silicone sacs currently on the market (note the longitudinal seam lines: real silicone sacs have to be injection molded). Latex sacs can release sulfur compounds as they age, which discolor plastics such as celluloid. Where color preservation is of paramount importance, 100% silicone sacs are the best choice. Most sacs currently advertised as "silicone" are actually PVC (vinyl) -- a material not compatible with celluloid: over time, PVC leaches a plasticizer which is known to attack celluloid). These sacs are shorter than their latex equivalents (14 and 15 sacs are ~70 mm long; 17 sacs, ~85 mm; 18½ sacs, ~80 mm). Sacs are sold by the bag, $10 for a bag of five sacs, or $20 for a bag of twelve assorted (three of each size). Bags of 25 sacs are $40; bags of 100 sacs are $100. The bag of 100 assorted sacs includes 25 of each size for $120.

NOTE: Silicone is much more permeable to air than latex, so pens with silicone sacs must be kept nib-up when not in use to prevent leakage. For the typical pen user, latex sacs are still the best option. More on choosing sac materials and their various pros and cons here.

Sac size Quantity (bags) (bags of 25) (bags of 100)

The PVC ("Pli-Glass") sacs that Parker used for their 51 Aerometrics are famously durable. Nonetheless, they do stain and darken, and eventually they will give out. We can now offer reproduction sacs made of the same material and as durable as the originals. Please note that these may stain when used with highly pigmented inks, and that they are not recommended for use in pens made of celluloid or cellulose acetate.
5 sacs for $10, 50 for $75, 100 for $100. ORDER

For quantity discounts, put the item in the cart, adjust the quantity, then click Recalculate.

Certain pens require special ink sacs, which we offer at $8 for a bag of three. Vacumatic sacs (Parker originally called them "diaphragms") come in three sizes. Confusingly, nearly all Vac-filling pens -- including most Parker Vacumatics, all Vac-filling Duofolds, and all Vac-filling 51s -- use "small" Vac sacs. Full-sized lockdown-filler Vacumatics use medium Vac sacs. Oversized lockdown-filler Vacumatics use oversize Vac sacs, though the medium sacs can be used in a pinch. More on Vac filler repair here.

Waterman Ink-Vue pens use another special sac. Standard and Deluxe Ink-Vue pens use standard-sized Ink-Vue sacs, while the little Lady Patricia Ink-Vue uses a smaller sac. Note that the late 5116 Ink-Vue with its one-piece barrel uses a completely different sac, that is not currently manufactured.

Sac type Quantity (bags)
Vac sac, small
Vac sac, medium
Vac sac, oversize
Ink-Vue sac
Ink-Vue sac, small

NOTE: To order 100 of an item sold in bags of 20, set the quantity in the cart at 5, then click Recalculate.

O-ring seals for Parker 51 Aerometric pens with a recess in the hood (shell). Do not install on pens with no seal recess in the hood! Newly manufactured to original specifications. Available in two sizes, for standard and Demi pens.
5 seals for $5, 20 for $15, 50 for $25

O-rings for Sheaffer pneumatic-fillers (these fit inside the end of the barrel, making an airtight seal with the plunger), newly manufactured to original specifications, now in long-lasting ethylene-propylene*.
20 for $10 or 100 for $35

NOTE: small rings fit Snorkels and most Touchdowns, including Imperials; large rings fit PFMs, 1949 Touchdowns (the fat first-year model), and Touchdown Tuckaways. (installation instructions here)

Point seals for Snorkel and PFM (these fit inside the nib/section assembly, sealing around the extending filler tube). Custom-made to our specifications in long-lasting ethylene-propylene*. These seals are of critical importance, for when old seals leak they may allow ink to be sucked into the pen's interior, causing the spring to rust and freeze up the mechanism: 20 for $18 or 100 for $65

* Ethylene-propylene seals should last at least twice as long as those made of ordinary rubber, which are vulnerable to oxidization, and especially the effects of ozone. Use only with pure silicone grease, keep away from petroleum-based lubricants.

Replacement ink sacs for Snorkel, Touchdown, and PFM repair are listed above. Correct sizes are as follows: #14, for Snorkels; #15, for slender Touchdowns, including Imperials; #17 or #17½, for Touchdown Tuckaways, PFMs, and fat-barreled first-year (1949) Touchdowns. Note that a half-size difference is only 1/128 inch (0.2 mm) -- not much more than the typical range of dimensional variation for dip-molded sacs.

(more on sac selection for pneumatic-fillers here)

Repair kits for Sheaffer pneumatic-fillers, $10 each. Snorkel and PFM kits each include three sacs, three point seals, and three barrel-plunger seals; Touchdown kit comprises a total of four sacs and four barrel-plunger seals, two each of each of the two sizes used. Sac lengths may differ from those shown in the illustrations above. Touchdown repair instructions may be found here; Snorkel and PFM instructions, here.

These kits are also available with silicone sacs at no additional cost (pros and cons of silicone sacs explained here).

General-purpose piston-filler seal replacement kit. Assortment includes 40 O-ring seals, 10 in each of four different graduated sizes. Easily installed replacements for traditional cork seals, use singly or in pairs, or in combination with greased felt washers. Will fit a wide variety of vintage European piston-fillers -- we have used these on pens by Aurora, Kaweco, Montblanc, Osmia, Pelikan, Soennecken, and others. $25/kit


(NOTE: This is the same assortment offered for Conklin Nozac repair below)

Piston seals for Pelikan 100 and 100N. Use in pairs as replacement for original cork seals -- will not fit pistons originally made to use synthetic seals.

Durable and easy to install, use with silicone grease for smooth action. Much faster than cutting and fitting a cork seal, no worries about cork seals drying out or shrinking.

Seals shown above installed in one of our transparent acrylic replacement barrels (at left) and in an original celluloid barrel (at right).


As above, but for vintage Aurora 88 fountain pens, replace original rubber and felt washers on piston.


Piston seals for Pelikan 100N, 400, 120, and 140 family pens. Secure snap-fit replacements for original synthetic seals, new manufacture, shown below mounted on Pelikan piston-filling mechanisms (not included). These seals are modeled on an original Pelikan piston seal design of the early 1950s. They come in two sizes: the clear and black seals are designed for precise sealing in barrels with a 9.0 mm inner diameter; the green seals are optimized for diameters of 9.1 to 9.2 mm.

In general, the larger green seals fit earlier production Pelikan 100N series pens with celluloid barrels, while the smaller clear and black seals fit late-production 100N pens with acrylic barrels as well as the 120/140/400 series pens. Unfortunately, there is much inconsistency in Pelikan barrel size, so we recommend that you order a mix of sizes -- let us know how much of each color to send.

$10 each or 5 for $40 (please don't forget to specify the color mix desired)


Piston seals for Conklin Nozacs (use in pairs). Kit includes 40 O-ring seals, 10 in each of four different graduated sizes. Sizes A and B will fit most standard-sized (5000-word) Nozacs, use C or D for oversize pens (7000-word). O-rings stretch over the piston head, seal tighter with less friction than any other seals we've tried. No more time-consuming gluing together of split cork! May also be used for a wide range of other piston-fillers. $25/kit


(installation instructions here)

Packing seals for Waterman safety pens (use two or three to replace the original cork shaft seal). Will fit pens up to #5-size (Waterman 45). Newly-manufactured in fluorocarbon rubber** for maximum durability and chemical resistance.
20 seals for $15


(installation instructions here)

Packing gaskets for plunger-fillers (used to replace original innards of Sheaffer or Eversharp packing units). Newly-manufactured in fluorocarbon rubber** for maximum durability and chemical resistance.
20 gaskets for $12 or 100 for $25


(installation instructions here)

** Fluorocarbon seals are extremely durable, resisting wear & weathering far better than standard synthetic rubber seals (estimated lifespan in industrial settings is up to 20 years, versus 2 to 5 years for the standard synthetic rubber, butadiene).

Precision-cut styrene closure washers to complete plunger-filler gasket installation, used to reclose the packing unit. Custom-made to our specifications: 20 for $8 or 100 for $25


Long-necked applicator, perfect for applying solvent cement in plunger-filler repair -- also a superior filler for eyedropper-filling pens (the long, thin tube reaches further into the barrel, filling it more neatly):
$0.50 each, ten for $2.50


Sheet stock for plunger-filler piston washer seals, top-grade synthetic rubber, correct stiffness and thickness for optimal filling and long service. This is not an off-the-shelf product: the nonstandard thickness is the same as that of original Sheaffer plunger-filler piston seals, works equally well for contemporary Eversharp and Conklin plunger-fillers.


High grade industrial felt, 1/16" (1.6 mm) thick; 95% wool, tough and dense, used in packing units and in some piston seals, layered with rubber washers, the felt serving to absorb and retain the silicone grease that seals and lubricates the seal assembly. Not to be confused with fabric and craft store felt, which is thin and flimsy and insufficiently absorbent.
$4 for a 4" x 6" (10 x 15 cm) sheet.


For quantity discounts, put the item in the cart, adjust the quantity, then click Recalculate.