“I know it is probably classed as quite an ‘old fashioned’ bit, but I like to use a McGenis snaffle for jumping and working a horse if a plain snaffle does not suffice,” says international eventerMary King.

Mary discovered the McGenis many years ago when another rider said it was a useful “in between” bit. “It was so long ago I can’t remember who recommended it,” says Mary.

“I find it works very well if a horse is getting very strong in a snaffle, but won’t take a pelham. My next step used to be the vulcanite pelham, but some horses object strongly to the curb chain.

“I have show jumped both Star Appeal and King William in a McGenis and most of my novices wear one for the cross-country. They tend to take much more notice of this bit and respect the square mouthpiece and the rollers, so don’t lean on it. People sometimes look at it and imagine it’s a severe bit, but it isn’t at all and the fact that most horseswill go well in one is a great benefit.

“It’s certainly a bit that works well for me in many situations and I’m surprised that more people don’t use one when they need to try something stronger than an ordinary snaffle.”

The McGenis is a jointed plain ring or eggbutt snaffle with a “square” mouthpiece in which there are copper or brass rollers. These run parallel with the mouthpiece, though do not actually encircle it, as with the cherry roller.