Windshield Molding and Install Consumables: Sizing, and What a Job Costs

Most of what’s needed for a windshield job is tooling that you buy once. Molding, tape, setting blocks and daubers are the items you buy again every month, and molding is the only one you have to size correctly.

This guide covers the two molding families GT Tools sells, how the sizes are laid out, and what each consumable costs per unit so a shop can plan what to keep on the shelf.

Two Molding Families

The two names are Under Glass Molding and Universal Rubber Molding, and the difference is position rather than quality.

Under Glass Molding goes under the edge of the glass, and the line is sold for back glasses and body shop removal and replacement work. Its adhesive is clear rather than black, which GT Tools states blends with the frit and removes the need for black primer on the edge.

Universal Rubber Molding is the exterior trim around the glass. GT Tools states that it stays flexible in extreme cold and will not shrink, crack or fade.

Both families are synthetic rubber and both are made in the USA. Both are also stated to fit a 90 degree corner without mitering or notching, which is the claim that changes how a job goes, because a molding that has to be mitered at every corner needs four accurate cuts per windshield.

Under Glass Molding: Six Sizes

Size	Length	Price	Guide bar
5.5MM	75 ft	$44.10	Yes
6.3MM	75 ft	$44.10	No
7.1MM	75 ft	$44.10	Yes
7.1MM Medium Firm	75 ft	$44.10	No
7.9MM	75 ft	$44.10	No
9.5MM	75 ft	$44.10	Yes

Prices checked 30 September 2026.

Every size is the same price. Sizing is not a budget decision here. Order the width the vehicle needs.

Three of the six have a built-in guide bar. They are the PUGM2, PUGM3 and PUGM6, which are the 5.5MM, the 7.1MM and the 9.5MM. The guide bar is there to hold a consistent line along the edge, so those three do part of that work for you.

7.1MM comes two ways. The standard and the Medium Firm are the same width and the same price. The firmness is the only difference, so a technician who finds the standard too soft on a particular glass has somewhere to go without changing size.

Universal Rubber Molding: Seven Widths

Size	Length	Price
7MM	75 ft	$44.10
10MM	75 ft	$44.10
16MM	75 ft	$44.10
16MM Line Design	75 ft	$42.00
19MM	75 ft	$44.10
25MM	75 ft	$44.10
31MM	50 ft	$44.10

Prices checked 30 September 2026.

Check the length on the 31MM before you order it. Every other width in both families is a 75 foot roll. The 31MM is 50 feet at the same $44.10, so the price per foot is higher. At 75 feet a roll works out to $0.59 per foot; at 50 feet it is $0.88.

The 16MM Line Design is $42.00 against $44.10 for the plain 16MM, a difference of $2.10. It is the same width with a line along its face.

Reading the Sizes

The widths are listed in millimeters, with an inch equivalent given on three of them: 7.1mm is 9/32 inch, 16mm is 5/8 inch, and 19mm is 3/4 inch. The rest of the range is in millimeters only.

There is no vehicle fitment table for either family, so measure the gap on the car in front of you rather than ordering by model. That is the reason to keep two or three widths on the shelf instead of one.

Cutting the molding to length is a separate tool. Our guide to manual and powered molding cutting tools covers the Universal Molding Cutter at $39.90, which has a cast aluminum tray with engraved angle markings for straight cuts and 45 degree miters.

Tape: Holding the Glass While the Urethane Cures

Marcy molding tape does two jobs on one roll. Before the glass goes on the vehicle it protects the corners in transit, and after the glass is set it holds the panel in position.

Tape	Size	Price	Cost per foot
Marcy Molding Blue Tape	3 in x 300 ft	$26.50	$0.09
Marcy Molding Tape	1.5 in x 108 ft	$8.40	$0.08

Prices checked 30 September 2026. Cost per foot is the price divided by the roll length.

Per foot the two are almost the same, so the question is width and how fast you get through it. The 3 inch roll is 300 feet against 108 feet at twice the width, which is about five and a half times the material for $26.50 against $8.40.

Both tapes are perforated every 6 inches, so a technician tears a length rather than cutting it. Both also carry the instruction to remove within 24 hours, alongside a statement that the tape leaves no residue.

For holding molding rather than glass, the Molding Hold Down Tool is $46.00 for a 6-pack. That is a reusable tool rather than a consumable, so it goes on the shelf once.

Setting Blocks and the Foam Dam

Two small items control where the glass ends up and how far the urethane spreads.

Auto Glass Height Setting Blocks are $9.50 for a 72-pad pack. Each block is 1/4 inch by 1/4 inch by 1 inch with a self-adhesive backing, so it stays where the technician puts it along the pinchweld. The reason given is that even with high-viscosity urethane the glass can still sink too low into the bead.

Single Side Foam Installation Tape is $9.50 for 18 feet at 1/4 inch by 1/4 inch. It is a foam dam with adhesive on one side. Its job is stopping urethane from pushing too far into the vehicle when the glass goes in, which matters on vehicles where the bead would be visible from inside.

Those two are easy to confuse because they are the same price and the same 1/4 inch profile. The setting block controls height. The foam tape controls how far the urethane spreads.

Primer Daubers

Premium Wool Daubers come in two ball sizes, 1/2 inch and 3/4 inch. Both are 100% wool with a 5 inch stem, both are 100 per pack, and both are $10.50.

The product page provides a rule for usage: dip the dauber into the primer once, apply it to the glass, then discard it. The reason is contamination, since a dauber going back into the bottle takes whatever it picked up off the glass with it.

At $10.50 for 100, each dauber is 10.5 cents. Treating them as single-use costs almost nothing and removes a way to ruin a bond.

What the Consumables Cost Per Unit

Pack prices are not much use until you break them down. These are the published pack sizes divided by the published prices.

Item	Pack	Price	Per unit
Wool daubers	100	$10.50	$0.105 each
Height setting blocks	72	$9.50	$0.13 each
Foam installation tape	18 ft	$9.50	$0.53 per ft
Molding tape, 3 in	300 ft	$26.50	$0.09 per ft
Molding, 75 ft roll	75 ft	$44.10	$0.59 per ft
Molding, 50 ft roll	50 ft	$44.10	$0.88 per ft

Prices checked 30 September 2026.

One limit on this. Roll lengths and pack counts are published; how much of anything a single windshield takes is not. That depends on the perimeter of the glass and on how your technicians work. Multiply the per-unit numbers above by your own measured usage rather than by a rule of thumb.

Molding is the expensive consumable by a wide margin, at $0.59 per foot against $0.09 for the tape. Everything else on this page is pennies.

A Shelf List for a Working Bay

If you are stocking from nothing, this is the order it makes sense in.

Buy first. Two or three molding widths covering the gaps you see most, a 300 foot roll of 3 inch tape at $26.50, a pack of setting blocks at $9.50, and a pack of daubers at $10.50. Two rolls of molding at $44.10 plus those three items is $134.70.

Add when the job calls for it. Foam installation tape at $9.50 for the vehicles where the bead shows from inside, and the Molding Hold Down Tool at $46.00 once you are holding molding often enough to want six of them.

Reorder by eye, not by schedule. The daubers and the setting blocks last for dozens of jobs. Molding does not, and a roll of the wrong width is worth nothing until the right car turns up.

The full range is in the Moldings and Tapes collection. For what happens on either side of this stage, our guide to single-technician windshield installation covers setting the glass, and the auto glass blade guide covers getting the old glass out.

Frequently Asked Questions

What is the difference between under glass molding and universal rubber molding?

Position. Under glass molding goes beneath the edge of the glass, and its clear adhesive is stated to blend with the frit so no black primer is needed on the edge. Universal rubber molding is the exterior trim around the glass. There are six sizes of the first and seven widths of the second.

What size windshield molding do I need?

Measure the gap on the vehicle. Widths are published in millimeters and there is no fitment table by make and model. Under glass molding ranges from 5.5MM to 9.5MM and universal rubber molding from 7MM to 31MM. Every size is $44.10 except the 16MM Line Design at $42.00, so ordering the right width costs no more than ordering the wrong one.

How much molding is on a roll?

75 feet for every size except the 31MM universal, which is 50 feet at the same $44.10. That makes the 31MM $0.88 per foot against $0.59 for the 75 foot rolls.

What are setting blocks for?

Stopping the glass sinking too far into the urethane, which the product page states happens even with high-viscosity urethane. The blocks are 1/4 inch by 1/4 inch by 1 inch with self-adhesive backing, 72 to a pack at $9.50, and they go along the pinchweld before the glass is set.

What is the difference between foam installation tape and a setting block?

They control different things. A setting block sets how high the glass sits. Foam installation tape is a dam that stops urethane pushing too far into the vehicle, which matters where the bead would otherwise be visible from inside. Both are 1/4 inch and both are $9.50, which is why they get mixed up.

How long can molding tape stay on the glass?

The product pages say to remove it within 24 hours, and state that it leaves no residue. Both Marcy rolls are perforated every 6 inches so a length tears off rather than needing a blade.

Can I reuse a primer dauber?

No. Dip it once, apply the primer, then discard it, because a dauber going back into the bottle takes contamination with it. At 100 per pack for $10.50, each one is about 10 cents.

Do I have to miter molding at the corners?

Both the under glass and universal rubber moldings are stated to fit a 90 degree corner without mitering or notching. For cutting to length, the Universal Molding Cutter at $39.90 has engraved angle markings for straight cuts and 45 degree miters.

Browse the full range in the Moldings and Tapes collection, or reach the team at gtglass.com.