{"product_id":"sigma-filter-105mm-wr-ceramic-protector-ptc-21","title":"Sigma Filter 105mm WR Ceramic Protector PTC-21","description":"\u003ch2\u003eSigma Filter 105mm WR Ceramic Protector PTC-21 | A protective layer for your lens\u003c\/h2\u003e\n\u003cp\u003eWithout a protection filter, the front of your lens is directly exposed to dust, fingerprints and accidental contact. The Sigma Filter 105mm WR Ceramic Protector PTC-21 sits in front of the lens as a dedicated protective filter, so it suits photographers who want a barrier between the lens and everyday handling. Its 105mm size makes it relevant to lenses that accept a filter of that diameter; it isn’t a universal fit. The product’s ceramic construction is part of its design, while “WR” is included in its name. For a large-diameter lens you’d rather keep protected during regular use, this is a straightforward option to consider. It’s focused on protection, not on adding a creative effect to your photographs. Think of it as a practical layer at the front of the lens, rather than protection for the whole camera or lens assembly.\u003c\/p\u003e\n\u003ch3\u003eChoosing this protector\u003c\/h3\u003e\n\u003cp\u003eThe key detail to match is the 105mm filter size. If your lens takes that diameter, this filter can sit at its front; if it takes a different size, this is not the right fit. That makes the intended use clear: a protective filter for a specific, large filter fitting, rather than a one-size-fits-all accessory. The model name also identifies this version as the PTC-21, which is useful when distinguishing it from other filters in the range.\u003c\/p\u003e\n\u003cdiv class=\"specialist-note\"\u003e\n\u003ch3\u003eSpecialist Note\u003c\/h3\u003e\n\u003cp\u003eThis filter protects the front of the lens, not the rest of it, so I wouldn’t treat it as complete protection for your kit. The reason I’d consider it is its ceramic construction: it gives you a dedicated protective layer over the lens’s front element. The 105mm size is the practical detail to pay attention to; it suits a lens designed for a 105mm filter, and won’t fit every lens. I’d look at it for keeping that front surface covered during everyday shooting or storage. If your lens uses another filter size, choose a protector made for that fitting instead.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eBrand: Sigma\u003c\/li\u003e\n\u003cli\u003eProduct type: Ceramic Protector filter\u003c\/li\u003e\n\u003cli\u003eFilter size: 105mm\u003c\/li\u003e\n\u003cli\u003eDesignation: WR\u003c\/li\u003e\n\u003cli\u003eModel: PTC-21\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Sigma","offers":[{"title":"Default Title","offer_id":57512880800084,"sku":"AFK9E1","price":312.71,"currency_code":"EUR","in_stock":false}],"url":"https:\/\/www.htf-store.com\/it\/products\/sigma-filter-105mm-wr-ceramic-protector-ptc-21","provider":"Hard to Find Camera Store","version":"1.0","type":"link"}