Ajax Systems 143555.177.BL1 door opening detector, Black

Who this is for

For the installer — this is the door opening detector supplied under Ajax Systems part number 143555.177.BL1. Specify it by that part number.

The entries in the specification table are the ones held against this part number. Anything not listed there is not stated by us, and should be confirmed against the manufacturer's own documentation.

In plain English: this is a door opening detector made by Ajax Systems. The part number 143555.177.BL1 is the manufacturer's own code for this exact version of it.

Similar-looking items in the same family often differ only by a suffix on that code. If you are replacing something, match the code rather than the picture.

Buying this in the UK

We are a UK supplier and this door opening detector is sold and shipped from the UK. Prices are shown in pounds sterling.

This item is returnable under our standard returns terms. Faulty goods are handled separately and are never affected by a returns restriction.

We do not quote a warranty term for this part. Every supplier-stated term we have checked against the manufacturer's own document has turned out to be wrong, so we would rather say nothing than say something we cannot stand behind.

Ask us and we will check it for you. Your statutory rights are unaffected.

Stock on this line moves, and lead times move with it. Ask us for the current position before you commit to a date on site.

Questions we get asked

Is this the exact door opening detector I have been quoted? Check the manufacturer part number 143555.177.BL1 against your quote. That code is the only reliable identity for this item.

Is there a datasheet? Yes — the documentation attached to this listing was checked and names this exact part number. Documents that named only the family, or a different item, are not attached.

Can you check compatibility for us? Ask before you order and we will check it against the manufacturer's own documentation. We do not state compatibility that the record does not carry.

Why does the listing not answer every question? Because the specification held against 143555.177.BL1 answers some questions and not others. We would rather leave a gap visible than fill it with something we cannot show you.

What if I order the wrong version? Tell us the installation you are matching and we will work back to the part number with you. That is a faster conversation than a return.

Do you hold this in stock? Availability on this line changes through the week, so the honest answer is to ask us on the day. We will give you the current position rather than a general one.