The objective was to evaluate the rumen stability (RS; % of CP) and TTCPDig (% of CP) of rumen-protected Met (EBMet) and 2 commercial Met sources using in vitro techniques. EBMet is a 34% DL Met coated with saturated FA. Statistical analysis was done using JMP® and means compared using Students t-test with significance at P < 0.05. Nitrogen content of the residues was determined by Kjeldahl. Study 1 assessed RS in an IV system. EBMet samples were incubated in a Daisy incubator in Dacron bags with rumen buffer and rumen fluid for 16 h and RS content of EBMet was determined to be 81.5% (SEM = 5.37). Study 2 determined RS of EBMet samples, a pH sensitive polymer coated 76% DL Met product (Product A) and a rumen-protected 85% DL-Met (Product B). Samples were placed in flasks with 40 mL of rumen buffer and 10 mL of rumen fluid. Flasks were incubated at 39°C for 16 h under constant CO₂, then filtered with a 1.5 μm glass filter and N content of the residue was determined. The RS for EBMet, Product A and Product B was 88.6, 91.5 and 61.2% (P < 0.1, SEM = 7.14). Study 3 was conducted using an IV rumen + intestinal digestibility (ID) assay to assess TTCPDig in EBMet, Product A and Product B. Samples were incubated in rumen fluid + buffer and after 16 h of IV incubation acidified with 3M HCL to bring the pH to 2 and incubated for 1 h after addition of 2 mL of pepsin. Samples were neutralized with 2 M NaOH and an enzyme mix containing trypsin, chymotrypsin, lipase, amylase, and bile was added and incubated for 24 h at 39°C. Samples were filtered on a 1.5 μm glass filter and N content of the residue was determined. The EBMet, Product A and Product B showed a TTCPDig of 78.6, 91.7 and 50.9% (P < 0.001, SEM = 3.72). Study 4 was conducted to determine TTCPDig as in study 3 but in a different lab. The TTCPD differed among all 3 Met products, EBMet, Product A and Product B were 93.3, 85.9 and 79.7% (P < 0.007, SEM = 1.07), respectively. Methods were effective in determining differences between products with different types of Met protection. Data suggest EBMet is a rumen stable Met product with high ID as shown IV by RS and TTCPDig.