What Red Horse Products has to say: 

"A paint on sole conditioner especially helpful for foot odour in stabled horses.

Sole Paint has a somewhat sticky consistency similar to HoneyHeel but is thin enough to be painted onto the underside of the hoof and frog. We designed it when we realised that HoneyHeel, despite not having specific antifungal ingredients was nearly as effective at eliminating foot odour as Sole Cleanse Spray due to its ability to stay in contact with the area longer (and the honey in it!). However it didn't go very far at all so we needed another product that worked out less expensive to use but even more effective.

Due to it being a paint we can make it with a much higher concentration of Zinc Sulphate, Honey and add Zinc Oxide, Eucalyptus and Coconut oil to give it a very powerful effect. We recommend Sole Paint for stubborn foot odour and discolouration that can be treated at least weekly."