Can anyone recommend a well brought-up knees boot for road work?

Have got a HUGE IDX gelding who is 17.2 & 19yrs old. He does have the occasional stumble doing a tour and did have a bad fall final year. I have got through a few pairs of knee boots as they don't give the impression of being to last 5 minutes. The strap seems to be the first to go, if not they slip down and he treads on them!! Has anyone got any recommendations of knee boots they hold used or are still using? Thanks very much
I have leather ones which I use on my 17hh horse. He has fall with them on and they protected him and are still in use. I would only use the leather ones as they are the with the sole purpose ones which don't slip.
http://www.shiresequestrian.co.uk/shop/p...

these boots are great and they are also a brushing boot so you get double the protection
Answers:    i use cottage craft full leg boots they are a brushing boot and knee boot in one! full size fits my 17.2 warmblood smoothly!
I always preferred Protecto knee boots. Big D catalogs has a voluminous selection of boots to fit your needs.
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