I am glad I found the Reddiseals Ltd website the other week - mid June 2018 - All I wanted was an alternative (permanent) way of fixing glass in four steel frames with large rebates. I must've used about five kg. of putty four years ago and it's starting to crack and look unsightly, so I decided to purchase some triangular beading from Reddiseals, it's made from a composite material of wood and plastic with a 10 year guarantee. £28 for 4 3 m.lengths including postage and packing.
The standard shipping was 2nd to none, ordered on the Friday and delivered on the Tuesday. The very narrow delivery window was very convenient and I received my order within it. I've ordered online for quite a while now and I must say that this is the best arrangement I've come across, so well done Reddiseals
Waiting for the cooler weather now for fitting the glass, and, it's going to be a lot quicker than puttying!