CAPs Bravo 3 & Bravo 4 were hit hard on 6 Feb, around Da Nang. This is from Michael Peterson's book
The Combined Action Platoons: The Marines Other War in Vietnam
Published By: Praeger, 1989
"On the morning of 6 February, CAPS Bravo 3 & 4 came under attack by elements of the 31st NVA Regiment south of Da Nang. Bravo-3 received assistance form 1st Bn. 7th Marines (1/7), including tanks, in defending its position. Bravo-4 was attacked by two companies of NVA and, using reaction forces from CAPs Bravo-1, Bravo-2, and "D" Co. 1/7, defeated the enemy force, killing 34. Bravo-1 was then attacked. Assisted by a reaction force from A" Co. 1/7, the CAP Marines and PFs killed 18 NVA.
"At least one of the battles of the Da Nang CAPs --- involving CAP Echo 4 --- had all the qualities of a desperate last stand as a Thermopylae, as Corson put it. At 1400 hours on 8 February, E-4 was attacked by an entire NVA regiment three miles south of Da Nang on Route 1. During the ensuing 15 hour battle, 288 NVA were killed by the CAP, assisted by air strikes. During the battle, a 15-man reaction force from CACO E, Hoa Vang District, was wiped out. Only one Marine survived, and E-4 had to be extracted by helicopter when ammunition ran low."
NOTE: I have received a note from Jim Chaffee commenting on two CAP Units with which he is familiar. I have posted his comments both here and on Echo 4 pages as received. I welcome any additional information I can get to finish each story.