WRTL MRL6 Lantern Installations
The WRTL MRL6 was a mildly popular main road lantern throughout the UK. It's design pre-dates the WRTL branding, first being sold as the GEC Z8600 and Phosco P426. It could be seen running 100W-250W SON. The canopy is made from GRP (fibreglass), with the bowl being made of polycarbonate. Competition from Urbis' ZX series of lanterns, and Philips' fixtures kept this lantern's numbers low, but some areas of the UK used them extensively.
Burton-upon-Trent
Located around Manor Croft, are several wall-mounted installations, many of which support MRL6s.
An SGS203 occupies the right-hand bracket in the below image, a spot-replacement for an MRL6:
All of the MRL6s here have singed bowls, which I don't imagine are very structurally-integral anymore. A cut-out box is present beneath each lantern.
Lichfield
This 150W example was spotted on Swan Road (column E10)
A massive portion of the bowl has been melted away by a fallen-loose lamp, a known problem with these fixtures. The lamp was re-secured but the bowl wasn't replaced.
Tamworth
A few MRL6s exist around Ventura Retail Park, Tamworth. These are yet more examples with singed bowls. This one is located atop column T111 of Jolly Sailor Roundabout.