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NIWNIW 2-5/16 in Coupler Lock for Select Bulldog & Ram Couplers

2-5/16 in Coupler Lock for Select Bulldog & Ram Couplers

$109.98 USD
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NIWNIW 2-5/16 in Coupler Lock for Select Bulldog & Ram Couplers
  • NIWNIW 2-5/16 in Coupler Lock for Select Bulldog & Ram Couplers
  • NIWNIW CTT-B lock illustrated coupler profiles for select 2-5/16-inch applications
  • NIWNIW CTT-B enclosure and push-to-lock puck operation illustration
  • NIWNIW CTT-B coupler lock components in an outdoor trailer illustration
  • NIWNIW CTT-B inner bracket, outer enclosure and locking sequence
  • NIWNIW NIWNIW coupler lock illustrated cargo, boat, travel and flatbed trailer uses
2-5/16 in Coupler Lock for Select Bulldog & Ram Couplers

2-5/16 in Coupler Lock for Select Bulldog & Ram Couplers

$109.98 USD

A steel coupler lock designed around select 2-5/16-inch Bulldog and Ram couplers. Check the coupler profile as well as the ball size.

Before you choose
For select 2-5/16 in Bulldog and Ram profiles. Ball size alone does not confirm fit.

Free standard shipping

Currently shipping within the United States. 1–2 business days to process · 5–8 business days in transit.

Delivery details →

THE DETAILS THAT DO THE WORK

Coupler lock for select 2-5/16 in Bulldog and Ram profiles

NIWNIW 2-5/16 in Coupler Lock for Select Bulldog & Ram Couplers

Steel security body.

A carbon-steel enclosure and protected puck mechanism add a physical barrier around a compatible coupler. No lock guarantees protection against every attack.

Push-to-lock design.

Lock the mechanism with a push and use an included key for authorized unlocking. Three keys are included.

Select Bulldog and RAM couplers.

Designed for compatible 2-5/16-inch Bulldog or Ram couplers. Check the profile, latch and fit diagram before ordering.

Powder-coated finish.

Coated steel construction for outdoor trailer use. Keep the mechanism clear of debris and inspect it during use.

Coverage and clearance.

The enclosure shields the coupler connection. Verify surrounding hardware and clearance on your specific trailer; fit is model-dependent.

SPECIFICATIONS & COMMON QUESTIONS

CTT-B: match the exact Bulldog or Ram profile

This lock is for select 2-5/16 in couplers. Compare the collar, nose and lower lip, then check the space around the latch and nearby hardware.

The listed 4.6 × 4.4 × 8.4 in product dimensions are not a verified internal-clearance measurement. Do not use them as the maximum size of a coupler that will fit.

Compare coupler photos and model references →. If the model or profile is unclear, send top, side and front photos before ordering.

Specifications

ModelCTT-B
Coupler size2-5/16 in
Dimensions4.6 × 4.4 × 8.4 in
Weight10.25 lb
Compatible applicationsSelect 2-5/16 in Bulldog and Ram couplers; model-specific profile and clearance must match
Materials & finishCarbon steel, Powder-coated finish

Before you order

  1. Coupler identification: For select 2-5/16 in Bulldog and Ram couplers; the brand name and ball size do not establish universal fit.
  2. Compare before ordering: Match the actual coupler profile, latch position and surrounding hardware with the fit photographs and product dimensions.
  3. Intended use: A physical security barrier for a parked trailer. No lock guarantees prevention of every theft attempt.

Need a fit check? Contact NIWNIW with your equipment model, clear photos and measurements. Please wait for confirmation if any detail is unclear.

Shipping estimates · 30-day return policy and conditions

Common questions

Does it fit every Bulldog or Ram coupler?

No. Compatibility depends on the specific coupler shape and clearance. Compare the product dimensions and photographs with your coupler before ordering.

READY TO UNPACK

What's included.

  • Coupler lock with protected puck mechanism
  • Three keys

A CLOSER LOOK

See the details.

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COMPARE YOUR OPTIONS

A different fit for a different setup.

  • 5 stars: 7 (88%)
  • 4 stars: 1 (13%)
  • 3 stars: 0 (0%)
  • 2 stars: 0 (0%)
  • 1 star: 0 (0%)
A
Amazon Customer
Original marketplace: Amazon US
Source program: Amazon customer review
Reviewed variant: Not provided in source review
Security

It works great.

R
Ron Mitchamore
Original marketplace: Amazon US
Source program: Amazon customer review
Reviewed variant: Color: Blue | Size: 2-5/16 Inch
Safe and sound

I feel very comfortable now when we leave our trailer to explore the area that it will be safe. I would rate it as a 4 3/4, The only reason for not rating it a 5 is the key to lock and unlock the device faces the ground which makes it a little difficult to unlock.

G
Gregg
Original marketplace: Amazon US
Source program: Amazon customer review
Reviewed variant: Not provided in source review
HD Trailer Hitch Lock

This was better and heavier built then I expected. I really don't think it would be an easy device to try and get busted off. Recommend this one.

A
Amazon Customer
Original marketplace: Amazon US
Source program: Amazon customer review
Reviewed variant: Not provided in source review
Security

Great lock!!!!

D
Dominique Goodman
Original marketplace: Amazon US
Source program: Amazon customer review
Reviewed variant: Color: Black | Size: 2-5/16 Inch
Definitely works!

Fits like it should and is heavy. Keeps my trailer where I left it. Great quality for many $$$ less than the big boy brands.

M
Matthew G. Barnes
Original marketplace: Amazon US
Source program: Amazon customer review
Reviewed variant: Not provided in source review
Better product lower price!!!

Great product

s
shannon l green
Original marketplace: Amazon US
Source program: Amazon customer review
Reviewed variant: Not provided in source review
Good product

Good product

W
Writer
Original marketplace: Amazon US
Source program: Amazon customer review
Reviewed variant: Not provided in source review
Reasonable value but I wish they offered it without a lock for less money

Reasonable price and seems like a good value. The black finish rubbed off in one small area of the internal piece, but it's not an issue. That will happen eventually regardless of which coupler anti-left device you use. A few notes: I have a Mul-T-Lock TL100, so I cannot speak to the effectiveness of the puck lock that comes with this item, which feels very light. You should research the puck lock independently of this product. There is room for the Mul-T-Lock key, which is chipped, to function without obstruction. Chains being exposed is not an issue because anyone who wants to steal your trailer will bring their own chains.