The thickness is one of the reasons I don't like the SMB 3s..Like you said, all boots let in a little dirt, but with that thickness the boot doesn't fit near as well as the VenTech Elites and where the boot doesn't fit the leg dirt gets in and wedges between the boot and the horse's leg. So not only is there a dirt buildup under the boot, the thickness holds in all of the extra heat to the leg and can cause serious injury. The VenTech are lighter not flimsy, and more contoured to fit the horse's leg, which doesn't let much dirt in because it fits better. The reason they are "flimsy" is because the new material is breathable so the heat isn't held on the leg.The thickness doesn't have anything to do with the protection level and support....Companies create new and better things to replace the older things that don't work as well as the bettered products. Research says it all. http://profchoice.com/p-6396-customer-care.html
VenTECH™ Elite Sports Medicine Boots were designed specifically for either the front or rear legs. Generally, your horse will wear the same size on both front and rear legs, as the size difference was taken into consideration in the design, but measure to be sure. VenTECH™ Elites come in three sizes for both front and rear legs.
The SMB-3™ is available in three sizes with relatively the same cut and feel as the SMBIIŽ but we have added a Lycra binding at the edge to help keep the dirt out and cut it up a little higher in the front to work with a bell boot. .
How long can my horse wear Sports Medicine Boots?
Maximum wear time is four hours for all boots except boots with VenTECH™ technology. Those boots can be worn longer due to the breathable, ventilated neoprene and lining.
Now with VenTECH technology, the Elite Sports Medicine Boot is lightweight and multi-layered with a ventilated, limestone-based neoprene exterior and UltraShock lining. Ventilated neoprene conforms to your horse, allows heat and moisture to escape, and keeps your horse cool, comfortable and performing at its best. The boot provides 360 degrees of protection, safeguarding the cannon bone, tendons and soft tissue, and is proven to absorb over 26% of energy from hoof impact. The uniquely designed suspensory strap stretches with each stride, allowing full ankle movement and helping to eliminate hyperextension of the fetlock. The distinctive angle of this strap guarantees proper application, ensuring the boot provides maximum protection.
The SMB-3 is a hybrid between the two best selling protective boots: the original SMB II and the VenTECH SMB Elite. The exterior is constructed with Professional's Choice signature limestone-based neoprene. Together with an UltraShock lining, the SMB-3 safeguards the cannon bone, tendons and soft tissue, while absorbing energy from hoof impact. The slightly longer suspensory strap stretches with each stride allowing full ankle movement, and helps to eliminate hyperextension of the fetlock. The SMB-3 is cut back at the lower front to allow for proper fit when used with any Professional's Choice bell boot. Lyrca binding stretches to create a more snug fit along the top and bottom of the boot, helping to keep dirt out. Once again, the Professional's Choice motto is achieved, The more comfortable the horse, the better the performance