Hozelock gun thing blocked

Would one of these be any good? A flat rubber disc. We have had one for years ( not that colour) and it unscrews a multitude of items.

 

Thank you for suggestion. I have got the gun de locked using a compressor at my local garage. I actually don’t think the gun is designed to pull apart and it was a complete fluke I did manage with one. Anyway, happy days now have all 5 working properly again. Good excuse for a wee dram ( any excuse), cheers!

 

@hailbopp , glad you’re all sorted now.