Kit includes probes and O-Ring. Perfect for long haired dogs he probes are 1/2 inch (1.3cm) long. The kit includes 2 standard-length Contact Points and O-ring Built for the Field: SportDOG gear was designed by professionals who demand durable, no-nonsense tools that perform in real-world conditions without fail Trusted by Serious Trainers: Professionals rely on SportDOG for proven performance, consistent control, and expert-backed training guidance that gets results