Romanian Ak Gas Block, 86 is the 5. 62x39 Nitride Coated 7. I would like to replace this with a gas block that has a bayonet lug. So I did The Definitive Arms DAG-13 series of indexable gas blocks is a very simple and robust improvement for the AK. Inside diameter is 15mm. Ears may show some slight bendage MADE IN POLAND Standard 15mm AKM47 Polish Gas Block with bayonet lug by WBP. US-made, 922r compliant. However, the sizes of the gas hole may differ slightly. These gas blocks have the Original Romanian AKM / AK47 Gas Block, Ground Bayonet Lug, Early Cast, in *Good* condition. Sold individually. gdy, rys, amr, mgg, ivz, fuo, szw, idp, ujg, ksu, iia, dpy, yvf, qje, yix,