If you are sourcing server rails, King Slide and MetrixSlide will both come up, but they answer very different purchasing questions. One is the ODM supplier behind many tier-1 server brands; the other is a factory that publishes its specs, quotes in writing and ships single pairs. This page compares the two on the points that matter to a mechanical engineer or buyer: rail range, load, customization, tooling fees, lead time, MOQ and how you actually get a price.
The 30-second answer
King Slide is the benchmark for tier-1 OEM volume programs. MetrixSlide is built for teams that need engineering attention, fast iteration and transparent pricing.
Choose King Slide if you are a major server brand running a multi-year ODM program with the volume and schedule to absorb a formal development cycle. Choose MetrixSlide if you need a rail that fits a specific chassis or rack, a fitment proposal in a day rather than a quarter, no tooling fees on a few hundred pairs, or standard rails in days with an MOQ of one pair.
The mistake is applying a tier-1 OEM sourcing model to a project that does not have tier-1 OEM volume, or the other way around. If you are replacing a King Slide rail on an existing chassis, start with our King Slide alternative guide and come back here for the supplier-level comparison.
Side-by-side comparison
King Slide information is taken from kingslide.com as of September 2026; MetrixSlide figures are from our published product pages. Where King Slide does not publish a figure, the cell says so rather than guessing.
| Criterion | King Slide | MetrixSlide |
|---|---|---|
| Rail range (U heights) | Rail kits for server, switch, storage, UPS and KVM; U-height range not published | 1U to 10U: sliding (ball-bearing and friction), fixed/support, tool-less and screw-mount, universal and custom OEM/ODM |
| Highest published load figure | Not published (site states heavy loading meeting UL safety tests, no figure) | Nominal capacity of up to 180 kg per pair (formal test report at that load not yet available), MS-BBR-180 for AI/GPU and liquid-cooled servers |
| Customization threshold | Customization offered; volume threshold not published | Bracket changes, hole patterns, length and thickness with no MOQ on flexible changes |
| Tooling / NRE fee | Not published | No tooling (NRE) fee within the customization boundaries above |
| Sample lead time | Not published | Fitment proposal within 24 hours of receiving your drawing; drawing validation to sample in a few weeks |
| Public catalog, specs and drawings | No catalog, part numbers or spec tables on the website | Public product pages with specifications; fitment proposal reviewed by a mechanical engineer |
| Public pricing / quoting path | No public pricing; enquiry form only | No public price list; written factory-direct quote via the quote page |
| MOQ for standard rails | Not published; sold through OEM programs | 1 pair, ships in 3 business days |
| Certifications | ISO 9001, ISO 14001, ISO 45001, RoHS, RBA (per its website) | ISO 9001:2015 and ISO 14001 certified manufacturing base |
| Rack standards designed to | Not published | EIA-310-D, IEC 60297-3-100/-105, OCP Open Rack V3 |
| Typical customer | Major global server brands under ODM programs | Server and chassis makers, IDC operators, AI/GPU integrators, refurbishers |
Two things stand out in that table. King Slide's public site is built to start an OEM conversation, not to let you pick a part, so most of the numbers an engineer would want to compare are simply not there. MetrixSlide's site is built the other way around: the spec is the starting point, and the quote follows the spec.
Where King Slide is stronger
The market leader is the market leader. On these points King Slide is ahead, and if they matter to your program, weight them accordingly.
- Scale and track record. According to King Slide's website, the company has more than 30 years of experience in slide rails and serves as an ODM supplier to major global server brands. Their rails have been through more OEM qualification cycles than almost anyone else's.
- Patent portfolio. The site cites more than 2,000 patents. For a buyer, that is a deep library of locking, latching and tool-less mechanisms already proven at volume.
- Certifications. ISO 9001, ISO 14001 and ISO 45001, plus RoHS and RBA, according to their website. ISO 45001 and RBA are items some enterprise procurement teams require from a tier-1 supplier.
- Load testing. King Slide states that its heavy loading meets UL safety tests. The figures are not published, but the UL reference matters to OEMs that need that language in a supplier file.
- Product breadth within a platform. Ultra-thin rail kits, cable management arms as standard configuration, and kits for server, switch, storage, UPS and KVM equipment.
For a tier-1 brand launching a chassis family that will ship tens of thousands of units, that combination is hard to beat.
Where MetrixSlide is stronger
MetrixSlide competes on a different axis: how quickly and precisely a rail can be made to fit a project that is not a hyperscale program.
- Engineering attention from day one. Send a chassis or rack drawing and you get a fitment proposal within 24 hours, reviewed by a mechanical engineer. If you are cautious about sharing CAD, we cover how that works in sharing CAD with a rail manufacturer under NDA.
- Customization without tooling fees. Bracket changes, hole patterns, rail length and material thickness can be adjusted inside our existing tooling envelope with no NRE and no MOQ on those flexible changes. What is and is not covered is laid out in custom server rail cost and NRE.
- MOQ of one pair, shipped in three business days for standard models. That covers prototypes, pilot racks, spares and refurbishment work.
- Published specifications. Every standard model has a public product page with load rating, mounting type and U height, so you can shortlist before you talk to us.
- Heavy-duty capability. The MS-BBR-180 has a nominal capacity of up to 180 kg per pair for AI, GPU and liquid-cooled servers, although a formal test report at that load is not yet available. In our factory static-load test a rail pair is held under load at full extension for 24 hours, and the MS-FMR-2U-100 held 100 kg in that test. For how load ratings are defined, see server rail load capacity explained.
- Manufacturing precision. Chassis-side hole tolerance is held within ±0.08 mm on progressive-die stamping, with roll forming, tooling, assembly, inspection and packing all in-house.
- Mechanism details. A dual-lock anti-drop structure and a patented anti-sag slide structure that keeps an extended chassis level during service.
On pricing, we keep it simple: factory-direct, no NRE within the customization boundaries, and a written quote back fast. We do not publish a price list either, since pricing depends on quantity, finish and configuration, but you will not have to enter a program to learn what a pair costs.
Which one fits your project
Match the supplier to the shape of the order, not to the brand name.
Tier-1 OEM volume program
A global server brand launching a chassis family with a multi-year forecast and a formal supplier qualification process. This is King Slide's home ground. The patent library, ISO 45001, RBA and UL-tested loading are all built for this buyer. MetrixSlide fits here only as a second source or for a regional variant that does not justify a full ODM cycle.
Chassis maker ordering a few hundred pairs
You build your own 2U or 4U chassis, sell a few hundred to a few thousand a year, and need a rail with your bracket and hole pattern. A volume program is the wrong tool for this order. MetrixSlide can adapt bracket geometry, hole patterns, length and thickness without tooling fees and validate fitment against your drawing within 24 hours. Start on the custom server rail solutions page.
AI/GPU integrator
You are racking multi-GPU or liquid-cooled nodes that weigh far more than a classic 2U server and need a published load figure for your design file today. The MS-BBR-180 gives you a nominal capacity of up to 180 kg per pair on a public page, although a formal test report at that load is not yet available. King Slide's site states UL-tested heavy loading but does not publish the number. Our heavy-duty rails for GPU and AI servers post explains what to check beyond the headline number.
Refurbisher needing replacement rails
Servers arrive without rails, or with rails from mixed generations, and you need something that fits, ships in days and needs no volume commitment. Some OEM rails, for example the Chenbro 84H341300-002 made by King Slide, do surface on eBay, Newegg and Amazon, but availability and generation matching are inconsistent. MetrixSlide's MOQ of one pair and 3-business-day shipping on standard models were designed for exactly this case. Read replacement server rails: functional equivalent vs copy before you order.
IDC with non-standard rack depth
Your cabinets are deeper or shallower than the rails your servers came with, or you mix square-hole, round-hole and threaded racks across halls, and you need modest quantities per hall. MetrixSlide rails are designed to those standards, support square 9.5 mm, round and threaded (M5, M6, 10-32, 12-24 style) holes, and length can be adjusted without NRE. See rack mounting depth vs rack depth vs chassis depth for how to measure.
How to evaluate any rail supplier
King Slide's website lists five points for selecting a rail kit. They are the right five, and they apply equally to King Slide, MetrixSlide or any other manufacturer.
- Space between rack and chassis. Measure the gap between the rack posts and the chassis side wall. It sets the maximum rail thickness and decides whether an ultra-thin rail is a requirement. Ask for installed thickness in writing.
- Chassis dimension and weight. Length, U height and fully loaded weight, not the empty chassis weight. Then check the supplier's dynamic and static ratings against that number with margin.
- Travel length. How far the chassis needs to extend for service. Full extension, over-travel or partial extension changes the design and the rating at full extension.
- Locking mechanism. Which positions lock (closed, fully open, intermediate), whether the locks are on both sides, and how a technician releases them. A dual-lock anti-drop design is worth asking about explicitly.
- Tool-less assembly. Whether the rack side and the chassis side install without tools, and whether one person can do it. Tool-less is not always the right answer; tool-less vs screw-mount rails covers when it is.
We add one procurement question: can you get the numbers for the first four before you commit? Needing an OEM program to answer is fine for a program, not for a pilot. Our server rail compatibility checklist turns these points into a form you can send to any vendor.
FAQ
Is MetrixSlide a drop-in replacement for King Slide rails?
Not as a blanket statement. Rails are matched to a specific chassis and rack, not to a brand. Send us the chassis or rack drawing and we return a fitment proposal within 24 hours saying whether a standard model fits or a bracket or hole-pattern change is needed. The King Slide alternative guide walks through the process.
Does King Slide publish specs or prices for its server rails?
According to King Slide's website as of September 2026, no. Server rails are presented on a single page with selling points, and the only path is an enquiry form. There is no catalog, part number list, spec table or price on the site, which is consistent with an ODM model.
What is the highest load rating MetrixSlide publishes?
The MS-BBR-180 has a nominal capacity of up to 180 kg per pair and is intended for AI, GPU and liquid-cooled servers; a formal test report at that load is not yet available. Our tool-less ball-bearing kit MS-TLS-120 has a specified capacity of 120 kg per pair. In our factory static-load test a rail pair is held under load at full extension for 24 hours, and the MS-FMR-2U-100 held 100 kg in that test.
Does MetrixSlide charge tooling or NRE fees for custom rails?
Not within our customization boundaries. Bracket changes, hole patterns, rail length and thickness are adjusted with no tooling fee and no MOQ on those changes. Requests that need new tooling are quoted separately, and the fitment proposal tells you which category you are in.
What certifications and standards does MetrixSlide hold and design to?
Our manufacturing base in Hunan, China is ISO 9001:2015 and ISO 14001 certified. Rails are designed to EIA-310-D, IEC 60297-3-100 and -105, and OCP Open Rack V3, and we have shipped to more than 60 countries. King Slide, per its website, holds ISO 9001, 14001 and 45001 plus RoHS and RBA.
Next step
If your project is a tier-1 volume program, King Slide is the benchmark. If you need a rail that fits, a spec you can read today and a quote you can act on this week, send us your chassis or rack drawing through the quote page and expect a fitment proposal within 24 hours. For heavy AI and GPU nodes, start with the MS-BBR-180 heavy-duty GPU server rail; for anything with a custom bracket or hole pattern, see custom server rail solutions.
King Slide is a trademark of King Slide Works Co., Ltd. Dell and PowerEdge are trademarks of Dell Inc. HPE and ProLiant are trademarks of Hewlett Packard Enterprise. Other brand names are the property of their respective owners and are used only to describe compatibility or comparison. MetrixSlide is not affiliated with, endorsed by, or sponsored by these companies.
