Features: Hybrid Technology: BQEYZ Spring 2 adopts drivers including 9 layers piezoelectric for more detail and fast trebles, 13mm coaxial dynamic for deep sub-bass, and balanced armature which is smooth with great tonality. Gorgeous Sound Quality: BQEYZ Spring 2 is suitable for HiFi Audiophile and music lovers for its superb clarity with excellent reproduction of mid, decently high, fairly deep bass frequencies, wide and details. Detachable Cable: Upgraded 0.78mm 2pin pluggable design with 4-strand 224-core single crystal copper wire brings more powerful signal transmission. 2.5mm, 3.5mm, 4.4mm - 3 plug types are optional. Comfortable to Wear: Spring 2 earphone shells are made of lightweight aluminum with 5-axis CNC process and 2-step anodization. Black and Green colors are available. Small housing only weighs 6.2 grams that comfortable on your ear to enjoying music. Package Includes: 1 pair of in-ear earbuds, 6 sets of silicone ear tips (including atmosphere for bass and reference for human voice), 1 pair of foam ear tips with a small box, storage case, upgrade removable cable, and a dust brush.