"Although this is slightly more expensive than the flat ring spanner I would thoroughly recommend this. It feels like it will last a few generations. It undid my old immersion heater with ease. I managed to thread the mains lead through the socket and still undo it so no need to remove the cabling first - once unplugged! This is twice the price for 10 times the quality."
"removed my heater in no time. fitted the new one. In all it took me about five minutes excluding draining tank. you always get someone who expect something for nothing and then moan about it !!!!!!!!!!!!!!"
"Spanner fitted perfectly after a few burrs were lightly filed off. Much stronger than a pressed steel cranked spanner, it removed the old heater and replaced the new one on a foam insulated cylinder with no trouble at all.
"Very good bit of kit, bought this to try & remove my old immersion heater, unfortunately the heater was well & truly stuck to the point on bending the “tommy bar”. However this is a great tool at a reasonable price and will not damage the cylinder lagging, unlike the spanner type."
"I try this box spanner after buying Ring spanner to remove Heater. Has they was no room to turn Ring spanner and was bend the top of tank the box spanner was larger than the ring spanner by 1mm and slip round heater nut till filling gap with 2p coin one of the flats work great after that"
"I would just like to add the other comment here. The spanner fit my old immersion element and the new one (from Screwfix) just fine. The old one was hard to get out, but the spanner did it without chewing the nut up or slipping. It it slips when putting in the new element, you're doing up too tight!"
"This is a sturdy tool; but it was no help to me. Even after neatly removing the washer from under it; our old-style heater wouldn't shift. This 87mm-across box-spanner turned on the 82mm-across heater element, without moving it. Screwfix' instructions do not cover removal of old heater element at all; but instead skip from disconnecting wiring to cleaning the thread, and fitting a new element! I had to drill a line of holes across the head of the old heater; then carefully cut and file to split one brass shoulder and thread entirely. Then, using my 12" Stanley FatMax waterpump pliers, I could squeeze the split-line enough to unscrew the thing. The Screwfix box-spanner's cost, in both time and money was all wasted: as I had to use my other tools, and ingenuity, to get the job done. This spanner is no use on tighter old-style rounded-corner octagonal heater elements."
"The spanner does not fit easily and snuggly on the immersion heater nut - you have to tap it on. Having said that it did the job and was very cheap compared to others like it, so I'm happy. If I were a professional plumber I might go for a better quality product."