I believe the reg style ADV is intended to used as a MAV for dil.they seem to have only one MAV ? right ???
My new TOS lungs arrived four hours ago today from ISC whence the smug look on my face.
This is from a post I put on a different chain:
OK so I was able to borrow some of the ISC TOS CL from the local Meg instructor and took them out for a dive weekend where I ended up doing 4 dives with them with max depth of 190 with a run times around 70-100min. My overall impression so far is that for me, they are trying to solve a problem which I believe does not exist (for me). They are very easy to set up and they do free up a bit of the chest area however they are also wider and thicker to allow for the lung volume to be close to the standard CL. This larger size makes them fit closer to my ears and I found that the CL rub against my hood which is a bit annoying. As well I think the WOB is harder than the standard CL, however this may just be a set up or T Piece position issue. I was able to use the standard plunger style ADV which worked as well as it does in the standard CL so I did not have to use the rather large ADV that come with the TOS CL. The manual add valve for the O2 was also difficult for me to reach as it is placed higher on your chest to allow for the short CL length which I did not like at all because I run a HCCR in manual mode so I am using the add button regularly throughout the dive. For me I will be sticking with the standard lungs as I am quite happy with them and used to where everything is. I am glad I was able to borrow a set before I bought them (thanks Dave T).
Hi when you say that "The manual add valve for the O2 was also difficult for me to reach " would this cus you mat have it to far back ?
I have not used these yet in fact I only saw these recently at here at OZ-teck for what I saw I was impressed as Lance said looks to be a improvement over front counter lungs, little bit concern with the size of the Vacuum ADV tho.

Hey Tony, Leon is working a modified Meg ADV to replace the vacuum ADV for the TOS CLs which will be no bigger than what you're already used to. The vacuum ADV works very well and you can trim the adjusting screw to find the sweet spot you like. It is big but it doesn't get in the way and is easy to use.
I'd say if it was difficult to reach the O2 MAV then the CLs were most likely not fitted and snugged down properly. They need to be fitted right up as high on the harness as possible and strapped down tightly. That seems to put them right where you need them.
Regards,
Lance
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