This 3M 391X air release tool is a retractable, very small pointed tip used to puncture a vinyl bubble and release the trapped air.This is a video that Fellers, the world's largest wrap supply company, asked The Wrap Institute to make for their catalog.
These two classes of consonants are the plosives and fricatives. Plosives are the kinds of sounds usually associated with the letters p, t, k; b, d, g, in which air flow from the lungs is interrupted by a complete closure being made in the mouth.
A consonant digraph consists of two adjacent consonants that produce one sound. The digraphs sh, ch, and th represent unique sounds that are not usually associated with any individual letters of the alphabet. The digraphs kn and gn are associated with the sound of /n/, and the digraph ph is associated with the sound of /f/. Learning to recognize the consonant digraphs is very helpful to beginning readers and writers because many early reading words contain these special two letter combinations.