{"product_id":"solinst-407-bladder-pump","title":"Solinst 407 Bladder Pump","description":"\u003cp\u003eThe Solinst 407 Mk2 Bladder Pump is a pneumatically-driven groundwater sampling pump built around a flexible Santoprene bladder inside a rigid stainless-steel or PVC body. Compressed air or nitrogen from a surface control unit pressurizes the space between the bladder and the housing, collapsing the bladder and forcing the water inside it up through a check valve to the discharge line; venting the drive pressure lets the bladder re-expand and refill with fresh formation water through a second check valve. Because the drive gas only contacts the outside of the bladder — never the sample itself — the pump avoids aerating or degassing the water, making it a standard choice for VOC-sensitive, low-flow sampling under EPA protocols.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDo you have everything you need?\u003c\/strong\u003e The 407 Bladder Pump requires a separate compressed-gas source and control unit — such as Solinst's 464 Electronic Pump Control Unit and a 12V compressor or gas cylinder — to drive the bladder cycle; it does not operate on its own. Stainless-steel models are rated to 500 ft (150 m) below grade; PVC models to 100 ft (30 m). Replacement bladders, drop tubes, tubing, and compressors are available on the \u003ca href=\"\/products\/solinst-407-bladder-pump-parts-accessories\" title=\"Solinst 407 Bladder Pump Parts \u0026amp; Accessories\" rel=\"noopener\" target=\"_blank\"\u003eSolinst 407 Bladder Pump Parts \u0026amp; Accessories\u003c\/a\u003e page.\u003c\/p\u003e","brand":"Solinst","offers":[{"title":"1.66\" PVC x 2ft","offer_id":48181378351294,"sku":"117212","price":188.62,"currency_code":"USD","in_stock":true},{"title":"1.66\" PVC x 4ft","offer_id":48181378384062,"sku":"117357","price":232.94,"currency_code":"USD","in_stock":true},{"title":"1.66\" Stainless Steel x 2ft","offer_id":48181378416830,"sku":"117209","price":323.23,"currency_code":"USD","in_stock":true},{"title":"1.66\" Stainless Steel x 2ft - 316 SS Balls","offer_id":48181378449598,"sku":"117218","price":342.56,"currency_code":"USD","in_stock":true},{"title":"1.66\" Stainless Steel x 4ft","offer_id":48181378482366,"sku":"117236","price":426.4,"currency_code":"USD","in_stock":true},{"title":"1.0\" Stainless Steel x 2ft","offer_id":48181378515134,"sku":"117217","price":253.1,"currency_code":"USD","in_stock":true},{"title":"1.0\" Stainless Steel x 2ft - 316 SS Balls","offer_id":48181378547902,"sku":"117219","price":265.19,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0592\/9926\/6750\/files\/407-solinst-bladder-pumps-and-replaceable-cartridge.webp?v=1784665341","url":"https:\/\/envirotechonline.com\/products\/solinst-407-bladder-pump","provider":"EnviroTech Services","version":"1.0","type":"link"}