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Which glazing packers and shims to buy

Updated: 23 October 2026

You have a gap, a tape measure, and an amazon.co.uk search that calls six different objects a shim. A flat packer for a uPVC window, a horseshoe that slips around a screw, a wood wedge, a scored composite taper, a rubber furniture wedge and a thin hinge slip are not substitutes. This guide is the order of decisions: shape first, then a thickness you can check, then enough pieces of that thickness. The [shims comparison](/hub/diy-supplies/shims) lists the eleven packs and their prices. Prices below are the amazon.co.uk shelf prices in this set, in GBP. A qualifying purchase can earn us a commission at no extra cost to you. This was not a lab test.

You have a gap, a tape measure, and an amazon.co.uk search that calls six different objects a shim.

Our top picks

EVOGES EVOGES flat glazing packers, 42 mixed

Best overall

EVOGES EVOGES flat glazing packers, 42 mixed
8.8/10about £6.99
View offer
EETU EETU horseshoe shims, 200 mixed, Broadfix

Alternative

EETU EETU horseshoe shims, 200 mixed, Broadfix
8.4/10about £18.97
View offer
HuangXinyu HuangXinyu flat glazing packers, 72

Best value

HuangXinyu HuangXinyu flat glazing packers, 72
8.4/10about £5.99
View offer
On this page
  1. 1.Six things called a shim
  2. 2.Thickness, width and colour
  3. 3.How many to buy
  4. 4.What to skip

Six things called a shim

Name the gap before you trust the search word. A flat packer is one thickness you can stack, commonly 100 × 28 mm. A horseshoe adds a slot for a screw already in. The EETU bag is 200 pieces, 55 × 43 mm, 1 mm to 6 mm, made by BROADFIX, at about £18.97. Nelson's 24 wood wedges, 8 inches, about £9.99, are a taper you score and snap. A furniture wedge grips a leg. A hinge spacer, about 0.05 inch on the iPhox listing, is not a 6 mm frame packer. If the gap is under a table, read wedges for wobbly furniture. Thickness is the next question, not the star rating.

Thickness, width and colour

Measure in millimetres. This set steps from 1 mm to 6 mm, with no 10 mm piece. The BPF's May 2025 guide, a supplier rule of thumb, uses 1–2 mm for fine adjustment, 3–4 mm for ordinary spacing and 5–6 mm for heavier glass. Those bands are not a load rating. Glazpart says a setting block should be rot-proof, wide enough for both panes, near the quarter points, and clear of the drainage. EVOGES and HuangXinyu flats are 28 × 100 mm. A narrower packer can tip. Flat colour lists often run green at 1 mm through red at 6 mm. Horseshoe lists often start at yellow. A HuangXinyu review found red used for both 4 mm and 6 mm. Read the moulded size.
EVOGES EVOGES flat glazing packers, 42 mixed

Testsieger

EVOGES EVOGES flat glazing packers, 42 mixed
8.8/10about £6.99
View offer

How many to buy

Pack size follows the job. The EVOGES 42-piece flat pack is about £6.99, seven of each from 1 mm to 6 mm, with 4.7 from 347 reviews. It can run short of one thickness. The HuangXinyu 72-piece pack is about £5.99, twelve of each, with 4.7 from 74 reviews. You get more pieces for less money, and you still check thickness because the colours slipped. Fizzix offers 100 pieces at about £5.79 without length, width or material, and one review describes a taper with a slot. About 6 to 12 packers on a casement is a seller's rule of thumb, not a survey. Two hundred horseshoes suit a run of linings, not one window. A Screwfix box of 225 flats is a different product, not a cheaper copy of the 42-piece amazon pack.

What to skip

Skip a soft furniture wedge in a frame or a rebate. Pe&Hui, HONGLINSONG, Mistillion and Buwoek compress, and they are the wrong object beside a fixing. Skip Nelson as a window packer even at 4.7 from 2,418 reviews. Only three of 47 saved texts are headed United Kingdom. Kiln-dried wood is reasonable where you can see it. It is the wrong thing to seal into a wet reveal. The EETU bag states no load, so a 25 kN line from another Broadfix page does not travel with it. Onspeshow, about £14.99 for 12 scored wedges, has no star line. Skip a hinge shim unless the only fault is a rubbing leaf on a door that is not fire-resisting. The iPhox pack has no reviews.

Common questions

What thickness glazing packers should I buy?
Buy the thickness that matches the gap you measured, in 1 mm steps. In this set that means 1 mm to 6 mm, with no 10 mm piece. A supplier rule of thumb uses 1–2 mm for fine adjustment, 3–4 mm for ordinary spacing and 5–6 mm for heavier glass. Those bands are not a kilogram rating. Above 6 mm, stack known thicknesses or stop and look at the frame.
Is 28 mm the right width?
For a domestic flat, 100 × 28 mm is the size on the EVOGES and HuangXinyu packs and on the Screwfix Broadfix medium listing. The packer should support the frame depth or both panes. A 55 × 43 mm horseshoe is for a lining, stud or batten with a screw in the way. If the frame is deeper than the packer, the piece can tip when you tighten.
Why do two packs use different colours for 1 mm?
Flat catalogues often use green for 1 mm and red for 6 mm. Horseshoe catalogues often use yellow for 1 mm. The maps are not a British Standard, and these bags are not sold here as BS-approved or FENSA-approved. A HuangXinyu review found red on both 4 mm and 6 mm. If the dye looks odd, read the size on the piece.
When do I need a horseshoe instead of a flat?
Use a horseshoe when a screw is already in the gap and the packer has to sit around it. UK reviews of the EETU bag describe door linings, studs, tile battens and cabinet backs. Use a flat when you are placing packers beside the fixings before you drive them. A horseshoe is a smaller piece, stated at 55 × 43 mm, not a better glazing block.
Can a furniture wedge stand in for a glazing packer?
No. A furniture wedge is a short taper meant to grip and come out again. A glazing packer is a known thickness that stays put and should not creep under the glass or the frame. Soft rubber under a unit is the wrong setting block. If the window is the problem, stay with rigid flats or horseshoes in polypropylene.
Does a higher star count mean the right type?
No. The wood shims show 4.7 from 2,418 reviews, and that file is mostly not a UK window test. The flat pack with 347 reviews is the stronger glazing note in this set, and it is still the wrong shape for a hinge or a table leg. Read the type, the millimetres and the job named in the reviews.

Related pages

How to pack a window frame

Plastic packers or wooden shims

Shims

Best glazing packers for one domestic UK window job

Furniture levelling wedges for rocking tables and chairs

Sources

Public UK sources and the amazon.co.uk listings compared on this page. Scores dated 22 October 2026. Updated 23 October 2026.

  1. BPF Online — How to choose the right plastic packer (retrieved 22 October 2026)
  2. Fixfast — Plastic packing shims data sheet (retrieved 22 October 2026)
  3. Glazpart — Glazing accessories (retrieved 22 October 2026)
  4. NBS — BS 6262-1:2017 (retrieved 22 October 2026)
  5. Fix Direct — how glazing packers are used (retrieved 22 October 2026)
  6. SAJE — How to toe and heel (retrieved 22 October 2026)
  7. Wickes — fixing distances (retrieved 22 October 2026)
  8. NHBC — Section 5, first fix operations (retrieved 22 October 2026)
  9. Approved Document 7 (retrieved 22 October 2026)