46 C.F.R. § 160.002-2 Size and models.
Title 46 - Shipping
Each life preserver specified in this subpart is to be a: (a) Model 3, adult, 24 ounces kapok; or (b) Model 5, child, 16 ounces kapok. [CGD 72–163R, 38 FR 8118, Mar. 28, 1973]
Title 46: Shipping
PART 160—LIFESAVING EQUIPMENT
Subpart 160.002—Life Preservers, Kapok, Adult and Child (Jacket Type), Models 3 and 5
§ 160.002-2 Size and models.

