Traditional HATS™ and IPC-2221B "D" Coupons are Daisy Chain electrical coupons and can be electrically tested with other Thermal Shock/Cycling Technologies that electrically test Daisy Chains, including Dual Chamber. HATS™ Testers updated with HATS²™ technology can test the HATS²™ Single Via Coupon which requires a unique measurement system to accurately measure resistances below 0.001 Ohm. Currently no other accelerated Thermal Shock/Cycling Technology can replicate HATS²™ technology. The HATS™ Tester updated with HATS²™ Technology uses High Speed Air as the heat transfer (fluid) mechanism to heat and cool the test coupons along with a 4-wire resistance measurement system which guarantees high accuracy testing of the coupon nets. Other Thermal Shock/Cycling Technologies use different heat transfer fluid Mechanisms like Oil, Nitrogen, Sand or Circuit Conduction to transfer heat to the coupons which results in different heat transfer rates to the coupons than Air. Other Thermal Shock/Cycling Technologies use different electrical measurement techniques (2-wire, 3-wire, low current, etc.) and meters/switching systems that may not have the current capacity, accuracy or repeatability of the HATS™ tester. These differences mean that HATS™ Testing Technology and cannot be exactly compared to other non Dual Chamber Thermal Shock Technologies. HATS™ Testers use air as the heat transfer mechanism just like the tried and true method used by Dual Chamber thermal shock/cycling testers for the last 50+ years. HATS™ testers can test traditional HATS™ coupons with up to 144 daisy chain test nets per test run. HATS™ Testers updated with HATS²™ technology can test up to 252 nets (single via and daisy-chain) from a variety of test coupon styles. Accomplishing 1000 cycles of that many coupons/nets with other "high speed" technologies can take weeks if not months due to their limited test coupon capacity when compared to the HATS™ tester. The HATS™ tester can accomplish 1000 cycles of 36 to 72 coupons in less than a week. Carefully research the methodologies out there before you decide.