Yes, you can shoe only front with Öllöv rubbershoes.
The steelcore of the shoe is 6 mm and the total shoe inlduing the rubbershell is 15-16,5 mm thick, depending on size. The largest sizes are somewhat thicker. The horse quickly gets used to the new “higher” shoes. Some horses can stumble somewhat for a few days especially downhill, but after a few days the horse will be used to the different feel of the new shoe.
Yes the shoes can have 2 or 4 studs per shoe. Currently we only offer shoes without pre-drilled studholes, but during 2018 we will start offering shoes with pre-drilled holes. Farriers can watch our film on how to drill the holes. 5/16 studs work best for the shoes. We also offer suitable studs in our webshop.