How do I read an i-Size booster 100-150cm on the orange label?

How is a 100–150 cm booster label different from a 40–105 cm harness label?

Both can say R129 and both can be orange. They are not the same product class. A harnessed (integral) i-Size seat is type-approved with its own harness, often from about 40 cm to 105 cm. A booster under R129 is non-integral: the child is held by the car’s adult seat belt, and UN Regulation 129 does not grant that type approval below 100 cm.

GOV.UK splits the two families by mark: height-based seats show E + R129; weight-based seats show E + ECE R44. A 100–150 cm booster you are reading here is the height-based family. RoSPA’s types of seat table lists R129 phase-2 seating from 100–135 cm, with 135–150 cm as specific-vehicle in that summary — which is why the orange sticker’s category words matter as much as the centimetres.

Which? groups many i-Size child seats as 100–150 cm for reviews. The legal text on your shell may split that range across two categories. Read the sticker, not a review grouping.

Which fields on the orange sticker do I actually read?

What do “i-Size booster seat” and “specific vehicle booster seat” mean?

UN Regulation 129 defines them as two categories:

• i-Size booster seat — a non-integral seat with a backrest, aimed first at i-Size seating positions in the car handbook. The regulation’s notice wording is that it is approved for use primarily in i-Size seating positions. Instructions may also allow Universal seating positions if that does not conflict with the car interior.
• specific vehicle booster seat — not claimed for every i-Size position. The regulation’s own example mark is a device “not capable of being fitted in every vehicle”. You need the maker’s vehicle list.

The same shell can carry a combined mark. UN R129’s worked example is i-Size booster from 100–125 cm and specific-vehicle booster from 125–150 cm. That is why one orange cluster can show 100–150 cm while the small print changes category at 125 cm.

This page does not rank a high-back booster against a backless cushion. nidirect says to check the label on a backless booster and use it only if that label shows it is suitable for the child you are carrying.

How do I read a 100–150 cm booster label, field by field?

1. 1
   Confirm it is R129, not a Group 2/3 R44 sticker Find the E-circle. If the line is ECE R44 and a weight group (15–36 kg), you are on a weight-based booster, not an i-Size booster. GOV.UK treats that as the ECE R44 family.
2. 2
   Copy the stature in centimetres Measure the child standing, without shoes, and compare with the printed band. Do not start a non-integral booster below 100 cm if that is the approval floor, and do not go past the upper cm on that sticker.
3. 3
   Read the category words, not only 100–150 If it says i-Size booster seat, open the car handbook’s i-Size / Universal seating-position list. If it says specific vehicle booster seat, open the seat maker’s vehicle list for that model.
4. 4
   Check for a split at 125 cm or 135 cm If one line is i-Size to 125 cm and another is specific-vehicle to 150 cm, treat them as two approvals on one shell. After the cut-off, the fit-list rule changes even though the sticker still shows 150 cm.
5. 5
   Check any kg limit and the belt path If a maximum mass is printed, that limit sits beside the centimetres. Route the adult belt through the guides shown for booster mode — R129 belt paths are marked green on many seats, per Road Safety Scotland.

The label goes to 150 cm. GOV.UK talks about 135 cm. Which number am I reading?

They answer different questions. GOV.UK says children must normally use a child car seat until they are 12 years old or 135 centimetres tall, whichever comes first, and then wear a seat belt. That is the national rule about when a child restraint is required.

The orange label’s 150 cm is the type-approval stature for that booster. It does not rewrite the 12-or-135 cm rule, and the 135 cm rule does not stretch the sticker. If you are still using the booster, stay inside the centimetres (and any kg) printed on it.

In shortA 100–150 cm i-Size booster sticker is an R129 non-integral mark. Read E + R129, the centimetre band, and the category: i-Size booster seat versus specific vehicle booster seat. Do not treat it as a 40–105 cm harness label, and do not start below the printed centimetres.