Ham-Let® to Crestflo Cross-Reference: Interchange Guide for Let-Lok® & One-Lok® Fittings and Valves
Crestflo builds instrumentation tube fittings and valves that match Ham-Let fittings dimension for dimension, covering the Ham-Let® Let-Lok® and One-Lok® lines. That gives specifiers and buyers a quicker, cost-competitive source, and fit, form, and function don't change. The compression tube-fitting range earns its interchangeability through ASTM F1387 performance qualification. Instrument valves, meanwhile, are built to ASME B16.34 and whatever API standards apply. Materials run from 316/316L up through high-nickel and corrosion-resistant alloys, and every part carries heat-number traceability. Standard items sit in ready stock; specials get made to order. Either way, delivery runs 6-8 weeks.
Ham-Let®, Let-Lok®, and One-Lok® belong to Ham-Let (Israel-Canada) Ltd. as trademarks. Crestflo operates independently and carries no affiliation, endorsement, or sponsorship from Ham-Let. Every Ham-Let designation mentioned here simply identifies which part a Crestflo equivalent replaces. The terms "interchange" and "dimensional equivalent" capture that relationship, not "compatible," not "intermix," and never "genuine."
Send us your Ham-Let part list, and we'll turn it into a Crestflo interchange quote. Request a Ham-Let interchange quote.
Scope: Instrumentation Fluid-System Fittings & Valves Only
This cross-reference covers instrumentation fluid-system tube fittings and instrument valves: stainless and alloy compression, or ferrule, fittings and instrument valves. It doesn't extend to electrical wire ferrules, plumbing or copper compression fittings, or hydraulic hose brands.
Also Known As: Let-Lok®, One-Lok®, H-Series & Ham-Let Interchange Terms
People land on this interchange through a lot of different search terms. Ham-Let's twin (two)-ferrule tube fitting line goes to market as Let-Lok® (you'll also see it written let-lok, let lok, or letlok), while the single-ferrule line carries the name One-Lok® (one lok). Instrument valves fall under the H-Series designation. Plenty of other phrasings show up too: ham-let cross reference, ham-let interchange, ham-let equivalent, ham-let replacement, ham-let crosswalk, ham let cross reference, and the frequent misspelling hamlet cross reference, plus part-family terms like ham-let twin ferrule, ham-let single ferrule fitting, and ham-let compression fitting. They all boil down to one question: what's the Crestflo equivalent, and can I get it in the alloy and lead time I need?
How the Ham-Let Interchange Works: ASTM F1387 Basis
Interchange means a Crestflo part is a dimensional, form-fit-function equivalent, dimensionally interchangeable with the Ham-Let part it replaces. Same tube OD grip, same envelope, same end connection. It seats and performs in the existing installation. Does that make Crestflo interchangeable with Ham-Let? For the compression tube-fitting range, yes. That interchangeability is validated under ASTM F1387 interchange qualification, the performance standard for mechanically attached tube fittings: proof pressure, tube grip and pull-out, vibration, thermal cycling. Publishing an F1387 basis is rare. It's testable proof of interchange, the kind most alternatives never offer. Crestflo doesn't use the words "compatible" or "intermix." A Ham-Let fitting and a Crestflo fitting are each complete, qualified assemblies on their own, and Crestflo supplies the complete equivalent.
Let-Lok® (Twin-Ferrule) Tube Fitting Equivalents
Let-Lok® is Ham-Let's two-ferrule (twin-ferrule) instrumentation tube fitting line, the twin-ferrule half of the Ham-Let tube fittings range. Crestflo double-ferrule tube fittings match it dimensionally across the full configuration set: union, tee, elbow, cross, connector, reducer, adapter, bulkhead union, port connector, cap, plug, and nut and ferrule sets. Single and double (twin) ferrule designs are both covered, and ferrules come hardened or non-hardened to requirement. Sizes go up to 2" (50 mm) OD, and that's true across imperial-fractional sizing as well as metric tube fittings. Thread and end parity is broad too, covering NPT, NPTF, BSPT, BSPP, ISO-parallel, JIC 37° flare, SAE-ORB, tube-OD, socket-weld, and butt-weld.
One-Lok® (Single-Ferrule) Tube Fitting Equivalents
Crestflo makes a single-ferrule tube fitting line that matches Ham-Let's One-Lok® dimensionally. Same connection styles, same size range, and it spans 316/316L through the exotic-alloy options. If you're standardizing on a one-ferrule design, Crestflo's single-ferrule tube fittings fit right in.
Ham-Let → Crestflo Interchange Summary Chart
The chart below maps each Ham-Let line and part family to its Crestflo equivalent, covering product family, connection options, and alloy range. Verified part-number crosswalks come per line item, available on request. Unverified competitor-to-Crestflo part mappings, though, aren't something Crestflo publishes.
| Ham-Let line / family | Crestflo equivalent | End & thread options | Alloy range |
|---|---|---|---|
| Let-Lok® twin-ferrule tube fittings | Double-ferrule tube fittings | NPT · BSPT · BSPP · ISO-parallel · JIC 37° · SAE-ORB · tube-OD · socket/butt-weld | 316/316L to Inconel, Monel, Hastelloy, Duplex, Ti Gr2 |
| One-Lok® single-ferrule tube fittings | Single-ferrule tube fittings | As above, single-ferrule design | 316/316L to exotic alloys |
| Nut & ferrule sets, spares | Nut and ferrule sets, hardened/non-hardened | Imperial-fractional + metric | 316/316L to exotic alloys |
| H-Series needle valves | Instrumentation needle valves | Threaded or tube-fitting ends, 1/16"–1" | 316/316L to exotic alloys |
| H-Series ball valves | Instrumentation ball valves (2/3-way, L/T-port, trunnion) | Threaded or tube-fitting ends | 316/316L to exotic alloys |
| Valve manifolds | 2/3/5-way manifolds | Direct-mount + remote | 316/316L, 6Mo, Duplex, nickel alloys |
Reading a Ham-Let / Let-Lok Part Number
Ham-Let owns a proprietary ordering scheme for Let-Lok® and One-Lok® part numbers, one that encodes series, tube or thread size, connection type, and material all at once. Guessing at that mapping is risky, and a wrong substitution isn't something you want to discover later. Send your Ham-Let catalog part number or part list instead, the full printed number, or even just a photo of the marked part, and Crestflo will send back the exact equivalent. Start a lookup with the cross-reference lookup tool, or request your part-number cross-reference directly from the engineering team.
Ham-Let Valve & Manifold Equivalents (Needle, Ball, Manifold)
The Ham-Let H-Series instrument valves cross-reference to the Crestflo instrumentation valve range, sized from 1/16" to 1", with threaded or tube-fitting ends. Equivalents span several product types: needle valve equivalents, ball valve equivalents in 2/3-way, L-port, T-port, and trunnion styles, check and NRV valves, plus valve manifold equivalents built in 2/3/5-way configurations. Every Crestflo instrument valve carries qualification to ASME B16.34 and the applicable API standards. That's the right basis for this kind of qualification. Manifolds also go through 100% seat and shell leak testing before they leave the shop. ASTM F1387 covers different ground: it applies to the compression tube-fitting range, not the valve line.
Ham-Let Alloy Availability: 316/316L, Inconel, Monel, Hastelloy, Duplex
Alloy breadth is where Ham-Let equivalents earn their keep. Crestflo builds interchange parts across 316/316L stainless, 304/304L, and 904L. From there the range runs through Duplex 2205, Super Duplex 2507, 254 SMO, AL-6XN, and Alloy 20. Then it moves into the nickel alloys: Inconel 625 plus 600/601/718/825, Incoloy 800/800H/825, Monel 400 and K500, Hastelloy C-276/C-22/B-2/B-3/X, and Nickel 200/201. Titanium Gr2 rounds it out. Sour-service parts conform to NACE MR0175 / ISO 15156. Values follow the applicable material standard, and each one can be customized to the requirement at hand.
Why Crestflo for Your Ham-Let Interchange
Crestflo is the instrumentation division of a four-decade-old export house recognized by the Government of India, with an established delivery track record across the Middle East. It's a faster Ham-Let supplier and single source across the same interchange range. A Ham-Let interchange means F1387-grounded dimensional equivalence, plus delivery on a ready-stock basis for standard items and made-to-order for specials, typically 6-8 weeks (versus the 20+ weeks common among the majors), and a landed price that stays cost-competitive even after US duties. There's more: small MOQs, private-label and made-to-print programs, quality certified to ISO 9001 / 14001 / 45001 and PED, and heat/lot traceability on every part, with EN 10204 MTC 3.1 as standard and 3.2 on request. PMI and in-house NDT come as part of the package. Standard product comes from India; US or European melt is available on request, with full material traceability, and TAA or domestic-melt requirements are covered on the US-origin & compliance page. Distributors can become a stocking distributor across that same range.
Frequently Asked Questions
Does Crestflo make a direct equivalent to Ham-Let® Let-Lok® fittings?
Yes. Crestflo builds instrumentation double-ferrule (twin-ferrule) tube fittings sized to match Ham-Let Let-Lok parts dimension for dimension. The compression range interchanges cleanly, and that claim rests on ASTM F1387 performance qualification, not guesswork. Send over your part list and we'll confirm an exact match.
Is Crestflo affiliated with Ham-Let?
No. Crestflo is an independent manufacturer; it isn't affiliated with Ham-Let, nor endorsed or sponsored by the company. Ham-Let®, Let-Lok®, and One-Lok® are trademarks belonging to Ham-Let (Israel-Canada) Ltd.
What does "interchange" mean here?
A Crestflo part matches the Ham-Let part it replaces in dimensions, form, fit and function. Validated for the fitting range under ASTM F1387. Crestflo relies on the terms "interchange" and "equivalent," never "compatible" or "intermix."
How do I find the Crestflo equivalent for my Ham-Let part number?
Send in the full printed Ham-Let, Let-Lok, or One-Lok part number, or just snap a photo of the marked part, and Crestflo hands back the equivalent. No need to self-map anything. You can also start from the cross-reference lookup tool, or simply ask the engineering team for your cross-reference.
Can Crestflo supply equivalents in exotic alloys like Inconel, Monel, or Hastelloy?
Yes, that's the full range: 316 and 316L, Duplex 2205, Super Duplex 2507, 254 SMO, AL-6XN, Alloy 20, Inconel, Incoloy, Monel, Hastelloy, and Titanium Gr2. No exceptions. Every grade meets NACE MR0175 / ISO 15156 conformance for sour service.
What is the lead time versus Ham-Let?
Crestflo keeps standard items in stock and builds specials to order, so most deliveries go out in 6 to 8 weeks. The major brands can't match that; their customers typically wait 20-plus weeks.
Do Crestflo parts come with material traceability?
Every part carries a heat/lot number, yes, that's standard practice, and comes with EN 10204 MTC 3.1 documentation as a baseline, with 3.2 available if requested. Standard stock originates in India. US or European melt can be arranged on request, and full traceability comes with it either way.
Are Ham-Let valve equivalents available, and to what standard?
Yes. We supply needle, ball, check/NRV, and 2/3/5-way manifold valves ranging from 1/16" to 1", with threaded or tube-fitting ends. These instrument valves meet ASME B16.34 and the applicable API standards, but they're not qualified to ASTM F1387: that standard covers compression-tube fittings, not valves.
Are the interchange part numbers published?
No. Crestflo provides verified Ham-Let-to-Crestflo part-number crosswalks on request, handled per line item. Unverified mappings don't get published. Send in your cross-reference request, and the engineering team will confirm the equivalent part and send it back.
Ham-Let vs Swagelok, which should I cross-reference to?
Both are twin-ferrule instrumentation systems, and Crestflo maintains a separate interchange guide for each one. Ham-Let parts belong here, on this page. Swagelok parts don't; for those, turn to the Swagelok cross-reference.
Related Cross-References & Resources
Want to keep exploring? Check out the instrumentation fitting cross-reference hub, browse the master interchange chart, see why buyers choose a Ham-Let alternative, or compare the two head to head with Ham-Let vs Crestflo, side by side. When you're ready, request a Ham-Let interchange quote or request a sample.
The Crestflo Engineering Team reviewed this piece. For US inquiries, reach out to sales@crestflousa.com or call +1 346 594 9005. Houston, TX is home base.