The right size for a stock K40 bay, in borosilicate glass with a choice of metal-head or glass-head ends. Its spec sheet is thin, so you set the running limits yourself.
The XYNLHZQ tube gets the key numbers right for a K40. It is a 40W tube, 700mm long and 50mm in diameter, the same size as the tube a stock K40 ships with. The glass is borosilicate, which XYNLHZQ rates for high temperature and pressure.
Past that, the spec sheet is thin. XYNLHZQ does not publish a working current, a maximum current, trigger voltage, warranty terms or packing details. Parts of its feature text describe mirrors rather than a tube, so ignore those lines and work from the title figures.
None of this makes the tube a bad buy. The core of a 40W glass tube is standard, and a 700mm x 50mm tube drops into the same cradles as the stock one. It does mean you carry more of the checking yourself than with a tube that ships with a full electrical table, such as the TEN-HIGH 40W.
Check the bay anyway. K40 cases vary slightly, and the K40 dimensions page gives the stock figures to measure against.
| Spec | Value |
|---|---|
| Brand | XYNLHZQ |
| Rated power | 40W |
| Length | 700mm |
| Outer diameter | 50mm |
| Tube glass | Borosilicate |
| End type | Metal head |
| Other end option | Glass head |
| Design | 2022 new type |
| Glass rating | High temperature and high pressure resistant |
| Machine types | Laser engraving, marking and cutting machines |
| Materials | Acrylic, cloth, leather, bamboo, wood |
| Fits | 700mm x 50mm tube bays, including stock K40 |
| Current rating | Not stated by XYNLHZQ |
| Warranty terms | Not stated by XYNLHZQ |
XYNLHZQ makes this tube in two end styles: metal head, the version here, and glass head. Tube makers describe the trade-off in similar terms. The power is the same; the difference is how the ends hold up.
| End type | Makers' case for it | Watch for |
|---|---|---|
| Metal head | Harder to crack, more heat resistant at the ends | Seal quality where metal meets glass |
| Glass head | Better end adhesion and fewer gas leaks, especially in the cold | Glass ends are more fragile in handling |
TEN-HIGH, which builds both types, puts it this way: a glass head bonds better at the ends, especially in cold areas, with less gas leakage and longer life; a metal head is harder to crack and handles higher temperatures. Treat both as maker positions rather than settled fact.
Handle the tube by the glass body, never by the nipples or the end fittings. Support it along its length when carrying it; a 700mm glass tube flexes more than it looks and the ends take the strain.
Whichever end you choose, look at the seals the day the tube arrives. A good end joint is clean and even all the way round. Cracks, bubbles or a crooked fitting at the end are reasons to send the tube back before it ever holds water.
With no current rating from XYNLHZQ, borrow the numbers the K40 world already runs by. For 40W-class glass tubes, the long-standing rule is to stay at or under roughly 15mA, and lower for everyday work. TEN-HIGH, for comparison, specifies 10–12mA working and 15mA maximum on its tube of the same size.
Running above that ceiling may cut faster at first, but it is widely blamed for shortening tube life. With no published maximum to lean on, caution is the only safe setting.
How long the tube lasts is not stated either. Glass CO2 tubes in this class are commonly quoted anywhere from about a thousand to a few thousand hours. Current, cooling and storage decide where yours lands; see the K40 tube and supply guide for matching tube and supply.
Installation follows the standard K40 routine, with one extra check for the leads. If the tube arrives without leads attached, the high-voltage joint has to be made and sealed properly: wire wrapped on the electrode, soldered, covered with an insulating sleeve and filled with silicone. If that is beyond you, pick a pre-wired tube.
Use distilled water or non-conductive coolant, never tap water, and keep it cool through long jobs. Many owners aim for below about 20–25°C.
Budget for the extras a thin spec leaves out: a milliamp meter if you lack one, silicone and sleeving for the high-voltage joint, and fresh coolant. Put together, they make any 40W tube safer to run, not just this one.
Store the old tube's leads and clamps until the new one has run a few jobs cleanly. If something goes wrong in the first week, you can put the machine back as it was.
It is 700mm long and 50mm wide, the stock K40 tube size. Measure your bay to be sure, since cases vary slightly.
XYNLHZQ does not state one. Follow the usual 40W-tube rule: stay at or under roughly 15mA, and set it with a milliamp meter.
The power is the same. Makers describe metal heads as harder to crack and glass heads as sealing better, especially in the cold.
XYNLHZQ does not say. Get that confirmed first; if they are not, the high-voltage joint must be soldered, sleeved and sealed with silicone.