SDX55M

The Qualcomm Snapdragon X55 5G Modem is the baseband chipset used in the iPad Pro (11-inch) (3rd generation), iPad Pro (12.9-inch) (5th generation), iPhone 12 mini, iPhone 12, iPhone 12 Pro and iPhone 12 Pro Max.

This is the first baseband chipset in an Apple Mobile Device to support 5G communications, capable of providing download speeds as high as 7.5 Gbit/s.

it is also known as  in firmware.

iOS and iPadOS
1.00.03-5  14.1           (Build 18A8395) 1.14.04    14.2 beta 4    (Build 18B5083a) 1.14.05    14.2 RC        (Build 18B91) 14.2          (Build 18B92 & 18B111) 1.14.06    14.2.1         (Build 18B121) 1.31.02    14.3 beta      (Build 18C5044f) 1.31.03-4  14.3 beta 2    (Build 18C5054c) 1.31.03-5  14.3 beta 3    (Build 18C5061a) 14.3 RC       (Build 18C65) 14.3 RC 2     (Build 18C66) 14.3          (Build 18C66) 1.41.00    14.4 beta      (Build 18D5030e) 1.42.02    14.4 beta 2    (Build 18D5043d) 1.42.03    14.4 RC        (Build 18D52) 14.4          (Build 18D52) 14.4.1        (Build 18D61) 14.4.2        (Build 18D70) 1.57.02    14.5 beta      (Build 18E5140j & 18E5140k) 1.60.01-2  14.5 beta 2    (Build 18E5154f) 1.62.02    14.5 beta 3    (Build 18E5164h) 1.62.09    14.5 beta 4    (Build 18E5178a) 1.62.11    14.5 beta 5    (Build 18E5186a) 14.5 beta 6   (Build 18E5194a) 14.5 beta 7   (Build 18E5198a) 14.5 beta 8   (Build 18E5199a) 14.5 RC       (Build 18E199) 14.5          (Build 18E199) 14.5.1        (Build 18E212) 1.70.03    14.6 beta      (Build 18F5046e & 18F5046f) 14.6 beta 2   (Build 18F5055b) 1.71.00    14.6 beta 3    (Build 18F5065a) 1.71.01    14.6 RC        (Build 18F71) 14.6 RC 2     (Build 18F72) 14.6          (Build 18F72) 1.70.03    14.7 beta      (Build 18G5023c) 1.80.00    14.7 beta 2    (Build 18G5033e) 1.80.01    14.7 beta 3    (Build 18G5042c) 14.7 beta 4   (Build 18G5052d) 1.80.02    14.7 beta 5    (Build 18G5063a) 14.7 RC       (Build 18G68) 14.7          (Build 18G69) 14.7.1        (Build 18G82) 14.8          (Build 18H17) 14.8.1        (Build 18H107) 2.03.01    15.0 beta      (Build 19A5261w) 2.06.00    15.0 beta 2    (Build 19A5281h & 19A5281j) 2.07.01    15.0 beta 3    (Build 19A5297e) 2.08.01    15.0 beta 4    (Build 19A5307g) 2.09.05    15.0 beta 5    (Build 19A5318f) 2.09.10    15.0 beta 6    (Build 19A5325f) 15.0 beta 7   (Build 19A5337a) 15.0 beta 8   (Build 19A5340a) 15.0 RC       (Build 19A344) 15.0          (Build 19A346) 15.0.1        (Build 19A348) 15.0.2        (Build 19A404) 2.10.00    15.1 beta      (Build 19B5042h) 15.1 beta 2   (Build 19B5052f) 2.11.01    15.1 beta 3    (Build 19B5060d) 2.11.02    15.1 beta 4    (Build 19B5068a) 15.1 RC       (Build 19B74) 15.1          (Build 19B74) 2.11.04    15.1.1         (Build 19B81) (iPhone 12 mini, iPhone 12, iPhone 12 Pro and iPhone 12 Pro Max) 2.21.01    15.2 beta      (Build 19C5026i) 2.22.00    15.2 beta 2    (Build 19C5036e) 2.23.02    15.2 beta 3    (Build 19C5044b) 15.2 beta 4   (Build 19C5050b) 15.2 RC       (Build 19C56) 15.2          (Build 19C56) 15.2.1        (Build 19C63) 2.22.02    15.3 beta      (Build 19D5026g) 2.23.02    15.3 beta 2    (Build 19D5040e) 15.3 RC       (Build 19D49) 15.3          (Build 19D50) 15.3.1        (Build 19D52) 2.51.01    15.4 beta      (Build 19E5209h) 2.52.00-1  15.4 beta 2    (Build 19E5219e) 2.53.01    15.4 beta 3    (Build 19E5225g) 15.4 beta 4   (Build 19E5235a) 15.4 beta 5   (Build 19E5241a) 15.4 RC       (Build 19E241) 15.4          (Build 19E241) 15.4.1        (Build 19E258) 2.52.02    15.5 beta      (Build 19F5047e) 15.5 beta 2   (Build 19F5057e) 2.54.02    15.5 beta 3    (Build 19F5062g) 15.5 beta 4   (Build 19F5070b) 15.5 RC       (Build 19F77) 15.5          (Build 19F77) 2.54.01    15.6 beta      (Build 19G5027e) 15.6 beta 2   (Build 19G5037d) 2.70.00    15.6 beta 3    (Build 19G5046d) 2.70.01    15.6 beta 4    (Build 19G5056c) 15.6 beta 5   (Build 19G5063a) 15.6 RC       (Build 19G69) 15.6 RC 2     (Build 19G71) 15.6          (Build 19G71) 15.6.1        (Build 19G82) 15.7 RC       (Build 19H12) 15.7          (Build 19H12) 15.7.1 RC     (Build 19H115) 15.7.1        (Build 19H117) 3.02.00    16.0 beta      (Build 20A5283p) 3.04.00    16.0 beta 2    (Build 20A5303i) 16.0 beta 3   (Build 20A5312g & 20A5312j) 3.06.01    16.0 beta 4    (Build 20A5328h) 3.07.00    16.0 beta 5    (Build 20A5339d) 16.0 beta 6   (Build 20A5349b) 16.0 beta 7   (Build 20A5356a) 16.0 beta 8   (Build 20A5358a) 16.0 RC       (Build 20A362) 16.0          (Build 20A362) 16.0.2        (Build 20A380) 16.0.3        (Build 20A392) 3.06.01    16.1 beta      (Build 20B5027f) 16.1 beta 2   (Build 20B5045d) 16.1 beta 3   (Build 20B5050f) 3.07.00    16.1 beta 4    (Build 20B5056e) 16.1 beta 5   (Build 20B5064c) 16.1 beta 6   (Build 20B5072b) 16.1 RC       (Build 20B79) 16.1          (Build 20B82) 3.20.00    16.2 beta      (Build 20C5032e)