Kun 4/4 Collapsible Fully-Adjustable Comfort Contour-Curve Violin Shoulder Rest Fits 14" Viola - The all-around favorite 4/4 violin & 14" viola shoulder rest. Johnny Music also recommends this 4/4 shoulder rest for 3/4 violin & 13" viola + 7/8 & 13.5" violas for many instances with larger / longer 3/4 players; this may likely save you $ in the long run as there'd be no need to buy another shoulder rest when upgrading from the smaller 3/4 violin/13" viola, but do take note that this larger shoulder rest may or may not fit into the smaller-confines of certain 3/4-sized case, and may not be optimal for the more-petite 3/4 violin/13" viola player.
More KUN Shoulder Rests, Full-Size+ to Mini; click links below (may not work on phone browsers):
KUN 5/4 Viola 15"+ Shoulder Rest
KUN 1/2-3/4 Violin 12"/13" Viola Shouder Rest
KUN Mini 1/16-1/4 Violin 11" Viola Shouder Rest
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Shipping & Handling Note: The shipping & handling rates may be significantly impacted by current energy/material/transport situation-costs. The default shipping & handling option here is USPS First Class/Ground delivered in a 4"x4"x4" to 8.5"x5.5"x1.5" small-standard box or similar to accommodate this single-item, unless customer or supply demands otherwise; faster delivery option(s) availble including Domestic Priority 2-3 Day service.