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Bootlace ferrule sizes

Updated: 21 October 2026

The collar in your hand is red, the flex is marked 1.5 mm², and on the next reel a red collar means something else. Bootlace ferrule sizes are decided by the square millimetre on the conductor and on the sleeve. Colour only works after you know which of three sequences the panel, or the kit, is using. This page is that match. It is not a ranking of pliers. Which tool to buy, and what it costs, stays on the [ferrule pliers comparison](/hub/pliers/ferrule-pliers). Colour notes and the listing claims in this set were read on 19 October 2026. We did not measure a kit’s compartments ourselves.

The collar in your hand is red, the flex is marked 1.5 mm², and on the next reel a red collar means something else. Bootlace ferrule sizes are decided by the square millimetre on the conductor and on the sleeve.

Our top picks

KNIPEX Knipex ferrule pliers 97 72 180

Best overall

KNIPEX Knipex ferrule pliers 97 72 180
9.8/10about £35.96
View offer
Preciva Preciva square ferrule kit CP621200

Best value

Preciva Preciva square ferrule kit CP621200
9.6/10about £22.99
View offer
Preciva Preciva ferrule kit with 260 dual ferrules

Alternative

Preciva Preciva ferrule kit with 260 dual ferrules
9.6/10about £23.99
View offer
On this page
  1. 1.Match mm², not the plastic
  2. 2.DIN, French, and the sequence UK sellers call German
  3. 3.Twin ferrules
  4. 4.What the amazon kits actually put in the box

Match mm², not the plastic

Read the cross-section on the cable sheath, then take a ferrule marked with the same mm². The plastic collar is a colour flag. It does not set the bore. A smaller conductor in a larger sleeve crimps on air. A bigger ferrule is not a spare for a thinner wire. A red collar never names one size on its own. The number on the ferrule is the part you trust. Strip, squeeze and pull on how to crimp a bootlace ferrule.

DIN, French, and the sequence UK sellers call German

Three collar sequences turn up on UK ferrules. Termnex sets them out as DIN 46228-4, French practice associated with NF C 63-023, and a special sequence that UK sellers often call German. Some catalogues print “DIN 46288”. That is not the number to copy. The ferrule parts used for these collars are DIN 46228. For the sizes you open a kit to find, Termnex gives this split. At 0.5 mm², DIN and French are white, and the special sequence is orange. At 1.5 mm², DIN and French are black, and the special sequence is red. At 2.5 mm², DIN and the special sequence are blue, and French is grey. The clash is 1.5 mm²: black in DIN and French, red in the special sequence. A red collar is 1.0 mm² in DIN and French, and 1.5 mm² in the special sequence. Do not mix sequences in one row. Where a panel has no drawing, the printed mm² still beats the colour. The ferrule crimping tool buying guide only points you here.
KNIPEX Knipex ferrule pliers 97 72 180

Testsieger

KNIPEX Knipex ferrule pliers 97 72 180
9.8/10about £35.96
View offer

Twin ferrules

A twin ferrule is one sleeve for two conductors of a stated size, written as 2 × 1.5 mm². You use it when those two conductors must share one clamp. You do not push two random wires into a single bootlace. Two listings here claim twins. The AivaToba HSC8-6-4A says two types of twin are in the box. The Preciva at £23.99 claims 260 dual ferrules beside 1,000 singles. Other kits are silent, so assume singles only. A review of the DxCRIMP says a twin of 2 × 16 mm² will not enter the jaw.

What the amazon kits actually put in the box

A piece count is not a size chart. The Preciva CP621200 claims 1,200 ferrules, and reviews say the smaller sizes are used up first. A review of the AivaToba YXQ008-16-NEW describes about 250 of the smallest and five of the largest. The AivaToba six-side kit at £24.99 draws a different complaint: only one collar colour per size. That fails if the drawing wants DIN black at 1.5 mm² and the pouch has the red of the special sequence. A dozen of 1.5 and 2.5 mm² in one sequence matters more than a headline of 1,200.

Common questions

Is a red collar always 1.5 mm²?
No. In the special sequence that UK sellers often call German, Termnex lists 1.5 mm² as red. In DIN 46228-4 and in the French column, 1.5 mm² is black, and red is 1.0 mm². Red also repeats on other DIN sizes, so the colour alone never identifies one bore. Read the mm² on the ferrule.
What is the difference between DIN, French, and German colours?
They are three collar codes for the same millimetre sizes. DIN 46228-4, as Termnex lists it, runs white, grey, red, black and blue for 0.5, 0.75, 1.0, 1.5 and 2.5 mm². French runs white, blue, red, black and grey for those sizes. The special sequence often sold as German runs orange, white, yellow, red and blue. Do not mix them in one row, and do not cite DIN 46288 for this.
What ferrule goes on 1.5 mm² and 2.5 mm² flex?
Use a 1.5 mm² ferrule on 1.5 mm² flex, and a 2.5 mm² ferrule on 2.5 mm² flex, in the colour sequence the panel already uses. If the panel is DIN, 1.5 mm² is black and 2.5 mm² is blue in the Termnex table. If the panel uses the special sequence, 1.5 mm² is red and 2.5 mm² is still blue. The sheath marking beats a guess from the collar.
When do I need a twin ferrule instead of two singles?
Use a twin when two conductors of one stated size share a clamp and the terminal is meant to take that twin sleeve. The marking looks like 2 × 1.5 mm². Two ordinary ferrules side by side are not a twin, and two different sizes in one sleeve are not a twin. In this set, twins are claimed on the AivaToba square kit and on the Preciva listing that states 260 dual ferrules.
Will a tool marked 16 mm² crimp a 2 × 16 mm² twin?
Not from the title alone. A review of the DxCRIMP, whose selector includes a range up to 25 mm², says a 2 × 16 mm² twin is not in the assortment and will not enter the jaw. A 16 mm² single and a twin of two 16 mm² conductors are different pieces of metal. Offer the twin to the jaw before you strip both cables.

Related pages

Square or hex ferrule crimper

Ferrule pliers

Best ferrule crimping pliers, and when to skip one

Ferrule crimping tool buying guide: range, jaw, kit

How to crimp a bootlace ferrule: strip, squeeze, pull

Sources

Public UK sources from the research digest, last checked on 19 October 2026. Shelf prices and star lines are the amazon.co.uk figures in the display file. The price bands are this set, not a market average.

  1. IET Wiring Matters: terminal blocks and regulation 526.9 (retrieved 19 October 2026)
  2. GOV.UK: building work, replacements and repairs (retrieved 19 October 2026)
  3. IET: Part P FAQ for England and Wales (retrieved 19 October 2026)
  4. Electricity at Work Regulations 1989 (retrieved 19 October 2026)
  5. Knipex 97 72 180 product page (retrieved 19 October 2026)
  6. Weicon 10100513 data sheet (retrieved 19 October 2026)
  7. RS Online: crimp tools guide (retrieved 19 October 2026)
  8. Termnex: bootlace ferrule colour codes (retrieved 19 October 2026)