CURT 2-inch Trailer Coupler Class 2 for 2-inch Channel Zinc-Plated — 3,500 lb GTW, Posi-Lock

CURT K-5153 is a zinc-plated Class 2 straight-tongue trailer coupler that fits a 2" channel and secures to a 2" trailer ball, rated for 3,500 lb gross trailer weight and 500 lb tongue weight.

This CURT straight-tongue coupler is engineered to replace a worn coupler or finish a new trailer build with a dependable, easy-to-install locking latch. Built from punched, die-cut steel and coated in durable zinc plating, the K-5153 focuses on reliable performance—resisting corrosion and maintaining a snug, adjustable connection to a standard 2" trailer ball. It uses CURT’s Posi-Lock latch system for straightforward adjustment and the option to add a safety pin or coupler lock for extra security.

How does the K-5153 attach to my trailer tongue?

The coupler is designed to slide over a 2" wide straight trailer tongue beam and fasten using the existing bolt holes on the coupler channel. Its internal adjustable nut lets you fine-tune the fit around the trailer ball so there’s no play once tightened.

• Mounts to a 2" channel trailer tongue beam
• Fits a standard 2" diameter trailer ball
• Adjusts with an internal nut and Posi-Lock spring for a snug fit
• Installs with common hand tools—no specialty equipment required

What load capacities and class rating should I expect?

This model is rated as a Class 2 coupler and is suitable for trailers with a gross trailer weight up to 3,500 lb and a tongue weight up to 500 lb. These ratings match light-duty utility trailers, small boat trailers, and many lawn or landscape trailers—but always verify your vehicle and trailer ratings before towing.

• Gross trailer weight (GTW): 3,500 lb
• Tongue weight capacity: 500 lb
• Class 2 coupler designation for light-duty towing
• Compatible with standard 2" ball and common tow setups

How durable is the finish and latch mechanism?

The K-5153 uses a zinc plating that helps protect the steel from moisture, road salt, and grime—extending service life in wet or coastal environments. The Posi-Lock latch is simple to operate, locks securely around the ball, and accepts a safety pin or coupler lock for theft prevention and extra peace of mind.

• Durable zinc plating resists corrosion and surface wear
• Posi-Lock latch for positive engagement and easy operation
• Latch accepts safety pin or coupler-style lock for security
• Punched, die-cut steel construction for consistent strength

What should I know about installation and maintenance?

Installation is straightforward—slide the coupler onto the 2" tongue channel, align the holes, and secure with grade-appropriate fasteners. Periodic inspection and lubrication of the latch and adjustment nut help maintain a tight connection and prolong service life.

• Requires basic hardware to fasten to tongue channel
• Check and tighten adjustable nut after initial use
• Lubricate latch components periodically to prevent binding
• Inspect for corrosion or wear and replace when compromised

Who is this for: The CURT K-5153 is aimed at DIY trailer builders, ranch and landscape professionals, boat owners with small trailers, and anyone replacing a worn or damaged coupler on a light-duty trailer. If your trailer tongue is a 2" channel and your towing needs fall within a 3,500 lb GTW rating, this coupler delivers an adjustable, lockable, and corrosion-resistant solution backed by CURT’s limited lifetime warranty.