Per S&W this is the STANDARD sear housing block. Others are described as NO IL,NO MS and NO IL. do not have the features as this sear housing and are only available by sending the M&P back to S&W. THERE ARE NO OTHER OPTIONS FOR M&P OWNERS FOR A SEAR BLOCK ASSEMBLY. Mfg: Smith & Wesson
Smith & Wesson Sear Housing Block Assembly, Standard
$37.99
FITS: M&P (Semi-Auto), 9mm, .357, .40; M&P Compact, 9mm, .357 sig, .40