Alright clo value experts, help me deduce my response from Mammut. I like their Rime Pro jacket, but had never heard of their Ajungilak insulation before (it has 100g of it evenly throughout their jacket). Sent a query to Mammut and here is the response:

"Thermal Transmittance of Textile Materials (ASTM D1518--2003)
Test Result
Intrinsic thermal resistance (Clo) : 2.488

(100gr/m2)"

How would this break down in terms of warmth compared to Primaloft One, Sport, etc?

Thanks!

Apex is spec'd at 0.82 clo/oz/square yard so you'de need 3 ounce/square yard to equal 2.488 clo

Primaloft Sport is 0.79 so 3.15 ounce/square yard

Primaloft One is 0.92 so 2.7 ounce/square yard

Thanks for the response. I don't know if my math is correct...

100g = 3.527oz
1 square yard = 0.836 square meters
3.527 * 0.836 = 2.94
3 / 2.94 = 1.02
1.02 * 0.82

Ajungilak clo/oz/yard = 0.836

Is that accurate? Making Mammut's proprietary insulation just a little warmer than Apex? Or approximately 91% as warm as PL1?

My math agrees with yours - 0.84 clo/oz/yd2 : )

I don't know why we don't all use grams, meters, and m2K/W - it would be much easier

I bet that the variation from sample to sample is bigger than the variation between average Mammut, Apex, or Sport. One is a little better but it's so fragile - requires more quilting which may actually eliminate any advantage.