Photos show the item you will be receiving.  It has a 3/8" (10mM) capacity, and is a keyless chuck with the "Hand-tite" feature.  It is manufactured by Jacobs.  This fits many, but not all, DeWalt drills.  It is best to check your manual for proper chuck replacement sizing.  I have a list below to help, but it is probably not complete.  Your drill will need a 1/2" mount.  Some drill mounts are not 1/2", with 3/8" being a popular alternate size, and this chuck will not fit onto those mounts.  This chuck threads onto a 1/2"-20 mount. 

Compatible with the following: DeWALT: DW927, DW927V, DW928, DW929, DW952B, DW952, DW953V, DW953, DW954, DW955 Angle, DW958, DW960, DW960P, DW960W, DW960K-2, DW960K, DW965, DW965 Rt Angle, DW966, DW971, DW975B, DW975, DW991B, DW991,  DW991Q, DW108 1/8,  D21008K, D21008KG, D21009, DWD112, DWD115, DWD110, D21008, 1187 HD Keyless Chuck Drill

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