product description: Safe and reliable To protect your trailer and trailer hitch ball mounts from theft, this locking hitch pin is constructed of high-strength steel. easy to use Barbell-style locking hitch pins promote an impermeable appearance, deter theft, and are activated with a simple 1/4 turn lock for easy locking and unlocking as needed Versatile This receiver hitch comes with 5/8"diameter pins and 2.8"(~7.2 cm) of usable pin length and will fit almost any 5/8"(~5.1 cm) hole 2 x 2"(~5.1 cm) hitch receiver (not compatible with double wall receiver tube) water proof The internals of this padlock are easily protected from inclement weather with the included water and dust cover, while the entire padlock is corrosion-resistant with a durable powder-coated finish Contains two keys For your convenience, two keys are included on this trailer hitch. You can keep the spare key in a separate location in an emergency, or give it to your friend for help. Specification: Receiver Tube Size: 5.08 cm | Pin Diameter: 0.625. Material: carbon steel