Some of you guys probably know this but I deal in new old stock car parts for a job & have been for about 12 years now so obviously I have to use royal mail most days but only when I must (stuff up to 1kg), over 1kg the best service and cheapest is 'collect plus' 1kg+, or if its over 10kg or foreign then I use parcel2go. Over the years there has been loads of stuff go missing including parcels with tracking where the tracking just ends midway through its journey and no-one knows where it is, another I remember where the courier stuck the wrong label over my label which meant it went to holland instead of france resulting in a weeks messing around with a 3 way email/phone calls. Another where fedex (used to be my uk carrier) lost 3 25kg boxes and after about 1 week they were 'found' in scotland and 1 had been opened! I have just been looking through the folder of lost/missing items and so far this year I have: Lost by courier a 1960's clutch plate, delivered to asos clothing by mistake and lost (clearly not scanned). Lost by the post office since and including christmas: an oil filter, a book, 3 brake hoses in one parcel (sent recorded), 2 sets of automotive lamps, a clutch master cylinder, a gasket set (again recorded) and a thermostat. I also bought a r/c gasket off e-bay for the sud which never arrived either. It's obvious that the post office are employing thieves and I am sorry for the good people that work for them.
It causes me so many problems especially if its an e-bay sale with the paypal etc.
Also just to clear up 2 points... 1) recorded items can and will still go missing and do, recorded just means that IF it does get delivered it will get a signature at it destination and stops the customer saying he hasn't got it. 2) It is vertually impossible to make a claim for loss if you are a business as the post office will only pay you for what you paid for it and they want proof of this, so for someone like me it means I lose as most of my stuff is on the shelf for years or is bought as a job lot so its impossible to show a cost per item.
So it is more than possible these plugs (both sets) where sent and stolen by someone at the post office.
There is no need to use the post office for anything over 1kg as 'collect plus' do 1kg - 2kgs for £3.99 incl vat (cheaper than the post office and with tracking and compensation for free), no need to wait in for a collection either as you just take it to your local collect plus shop (usually a newsagents) which you can find on their website, they scan it and give you a receipt there and then showing the tracking and you can track it online, you can send up to 10kgs using their service. (i would post a link but unsure how to do it)