Do I need a vacuum ring to properly attach a VAC cylinder?

I’m planning to modify my JES extender into a VAC extender, but I find the autoextender parts too expensive (120+ dollars).
I found an ADS on amazon that has 3 sizes for cylinders and tubing for only 40 euros, but it doesn’t have the vacuum ring the autoextender comes with.
Based on the instructions on the ADS you just put the silicon sleeve on the penis then roll it over the cylinder.

Do I need this vacuum ring for this to work properly? If I do, are there any similar product/alternatives I could buy separately on ebay or amazon?

(The vacuum ring is that black thing on the second picture)

The short answer is yes. You can rig several types of bell or cup if your a DIY guy along with silicone but it’s so cheap to find something from eBay. So find the right size for your glans. Or you can just get a sleeve that would go over your glans around the noose to make your extender more comfortable. A gel toe protector, even a combination of micropore tape, cotton cloth or Tera band could do the trick. Not quite sure why you want to convert your extender to a vac extender. In my opinion, extender is extender, it’s all about comfort and slippage. Wrap around the noose should suffice.

What do I search for on ebay to find that? Vacuum ring inst exactly a specific name. What is that ring even made out of?

I want to convert to VAC because my glans get cold from the noose, and they are not very comfortable. From what I heard, a VAC extender doesn’t cut off circulation and is overall more comfortable and safer (although I head you can get blisters and edema, but taping apparently fixes that problem). I tried a couple different ways to attach the extender, and a few ways to wrap it, but everything slips off or is very uncomfortable.
I figure might as well try converting to a VAC extender, and if it doesn’t work well I can always go back to the noose.

I attached a picture of what I’m planning to buy, as you can see it has everything except that black vacuum ring thingy.

Sorry for late reply, busy week.

It’s called vacuum cup. Not sure if moderator will kill link so i truncated the main ebay address part look for vendor cocokv01, i bought from here before, quality and shipping is reliable. Go to totalman, measure your glans to know which size would be right for you. Tighter is better. You lose pressure and it makes the cup useless. You can get a bigger cup but you have to stuff it to make it tighter, or use silicone over it so I personally prefer tighter. Give yourself breaks to let your glans breathe. For less than 30, there’s a full set. Im planning to get link#2 myself. Im not affiliated with this vendor. I bought from ebay before so i had more flops at amazon. Good luck.

Totalman and TP had DIY cups tutorial. I saw one used a medicine bottle, a few saline caps, an eyelet hook then filled it with silicone to make it more comfortable. Im a handy guy but silicone ain’t cheap so unless i already have a project and it’s lying around my workshop, plus a bottle cap is not stealth either so anyhow.

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