This diaphragm is for AK-14RF or K-14A carburetors. These carburetors are used on M462, M14p, AI14 and other AI14 based engines. In aircraft such as YAK 52, YAK 18, Sukhoi and other.
The diaphragm is for recomended 6 yearly diaphragm replacement or in case of diaphragm malfunction.
Common problems are fludding (old stretched diaphragm) or fuel starvation (cracked diaphragm).