Master Lock 4688D Set Your Own Combination TSA Luggage Lock Review (2026)

Who this lock is built for

The 4688D is aimed at travelers who want one padlock that stays on a checked bag, backpack or packing cube for years without a key to lose. Because it uses a set your own combination instead of a keyed cylinder, there is nothing to hand out to a travel partner and nothing to search for at security. That makes it a natural fit for a single carry on or checked suitcase that a solo traveler locks and unlocks daily, rather than a shared family setup where several people need access at once. It also suits anyone who has lost a luggage key before and wants to remove that failure point entirely. Because the shackle is a flexible braided cable rather than a rigid steel loop, it also clips through the narrower double zipper pulls found on daypacks and toiletry bags, not just the wider loops on hard side suitcases.

The body, shackle and combination explained

Master Lock builds the 4688D around a 1 3/16 inch, 30 millimeter wide metal body that houses the combination wheels and locking mechanism. Instead of a rigid steel shackle, it uses a 1/8 inch, 3 millimeter diameter shackle made of vinyl covered flexible braided steel, about 1 1/2 inches or 38 millimeters long. That flexibility is the main design choice: it bends to reach through slightly misaligned zipper pulls that a stiff shackle would not clear. The lock is recognized as a TSA accepted design in 29 countries, meaning screeners who need to inspect a bag can open it with a master key, check the contents and relock it without cutting the shackle. It ships in assorted colors including black, blue, red and silver, so a household with several locks can color code them by bag or by family member.

Setting the combination and living with it on the road

Setting your own three digit combination is a one time task done before the first trip, after which the lock simply opens and closes on that code. The three small dials sit flush with the body, which keeps the lock compact but also means they can be fiddly to spin accurately with cold fingers or in the dim light of an overhead bin. Day to day care is minimal: wipe off grit after checked flights, since baggage handling exposes the shackle and dials to dust and occasional rough handling, and avoid forcing the dials if they feel stiff, since combination locks are more sensitive to debris than keyed padlocks. Because the shackle is a cable rather than a rigid loop, it also tolerates being looped through slightly larger openings, such as two zipper pulls plus a loop of webbing, which a solid shackle cannot do.

How it compares with Master Lock's keyed pack and budget cable locks

Within Master Lock's own TSA lineup, the 4683Q brass keyed four pack trades the 4688D's combination dials for a shared key, which opens faster but adds a second item that can be lost or left behind. The 4688D avoids that risk entirely since there is no key, though it means memorizing one more code alongside phone and door codes. Against unbranded budget cable locks sold simply as re-settable TSA locks, the 4688D carries the weight of a recognized manufacturer and a stated flexible braided shackle, while many generic listings do not specify shackle material or confirm the TSA program at all. The trade off is price: bargain cable locks typically undercut a name brand lock, and if a lock is lost or confiscated, that lower cost matters more to some travelers than brand recognition.

Verdict and who should look elsewhere

For a solo or couple's one bag setup where the priority is a dependable, keyless lock on a checked bag or daypack, the 4688D lines up well with its score of 8.1 out of 10 in this guide, built mainly on how well it fits the job and its value for the price. Travelers who want the fastest possible open and close, especially when sharing access with a travel companion, may prefer the keyed 4683Q four pack instead, since a key twist is quicker under pressure than dialing three digits. Anyone expecting a lock to stop a determined thief with cutting tools should also look at hardened cable or chain options, since this lock, like other TSA accepted luggage locks, is designed to deter casual tampering and satisfy airline and security requirements rather than resist serious force.

Frequently asked questions