My horse is not accepting steady rein contact – What could be the causes? 
Part 2: If it is the equipment.

Here you can read why ill-fitting equipment will prohibit a good rein contact. As this is also a nearly endless topic, we will limit the discussion to the head area for now, meaning mostly the bridle and bit. Moving forward with these Rosskur editions, we will enlarge the scope and also look the the parts further behind on the horse, like saddle and longing equipment.

I am sure, at some point you wore ill-fitting underwear or noticed rubbing seams of trousers, had on glasses that sat lopsided on your nose and made you mad? Then you can relate, how a horse might feel with an ill-fitting bridle. The head is the most sensible part of a horse, nearly all sensory organs are located here, a particularly large amount of nerves is close to the surface and there are close to no fat pads. Also energy channels (meridians) have their origin in the head or run along parts of the face and various acupuncture points with partly long distance effect are located in the hear area.