Lift upward on the Top Cocking Knob. This will allow the Venturi Bolt sliding from the rear of the Receiver. With the Venturi Bolt removed out of the Receiver, this allows easy access to clean with a squeegee. Make sure the hole on the Striker Bolt is facing upright when looking thru the Receiver. This will allow the Top Cocking Knob to correctly fasten with the Striker Bolt. Please note how the parts are removed for easy reassembly. Disassemble Rear Internals Lift upward on the Top Cocking Knob.This will allow the Venturi Bolt sliding from the rear of the Receiver. Remove the Quick Disconnect Pin. This will allow the Striker Plug and the markers internals to side from the Receiver. Remove the Quick Disconnect Pin when the markers in the decocked position. This way, the tension of the Striker Spring does not allow the markers internals to spring out. Placing your finger behind the Striker Plug before removing the Quick Disconnect Pin will prevent the markers internals to spring out. Remove items in order: Striker Plug with Velocity Adjuster, Striker Spring and Striker Buffer. Slide the Striker Bolt out of the rear of the Receiver. When the internals are removed it would be wise to clean any dirt or paint from the inside of the Receiver with a squeegee. Wipe clean the Venturi Bolt with a rag or paper towel. Apply some paintball oil on the Striker O-ring periodically. Reassemble Rear Internals Insert the Striker Bolt thru the rear of the Receiver with the o-ring facing towards the front of the marker. When inserting the Striker Bolt, apply pressure behind the Striker Bolt and at the same time pull on the Trigger to allow entry of the Striker Bolt. The hold on the Striker Bolt should be facing upright when looking thru the Receiver. This will allow the Top Cocking Knob to correctly fasten with the Striker Bolt. Insert the Striker Buffer flush with the Receiver and place the Stiker Spring thru the Striker Buffer. Insert the Quick Disconnect Ping thru the Receiver to hold the Striker Plug in place. Insert the Venturi Bolt thru the rear of the Receiver with the Top Cocking Knob. Press downward on the Top Cocking Knob to gain entry with the Striker Bolt. If the striker Bolt hole is not aligned upright, the Top Cocking Knob will not fasten correctly with the Striker Bolt. Use a small tool devise, to align the hole upright should the Striker Bolt turn when positioned back in the Receiver. The Quick Disconnect Pin must be properly placed thru the Receiver. The ball bearing on the pin must be visible thru the opposite end of the Receiver. To assure marker is assembled properly, follow the schematic drawing or position parts in order during disassembly. Parts assembled backwards or improper parts installed will or can cause the marker to malfunction. Never attempt to remove the markers internals while the CO2 / Compressed Air Tank is attached. Make sure to remove all paintballs and loader before disassembling the marker E-MR1 E-MR1s are the electronic counterparts of the MR1s. They are upgraded with: Electronic grips(E-grip), capable of firing 15 bps in 3 modes of operation: semi-automatic, full-automatic, and bursts 2-way adjustable triggers, adjustable to players's preferences Delrin bolts Removable adjustable shoulder stocks E-MR1s are available in matte silver or matte olive. MR1 Sniper The MR1 sniper is a long range counterpart of the MR1. The MR1 sniper is rated higher than the original marker for its superior accurracy to countless other markers. The MR1 sniper features a 16" barrel rather than a 12" on a standard model. Features and specifications MR1 Standard Features Military Style Semi-Auto Paintball Marker All Aluminum Constructed Body Ergonomically Designed Aluminum Trigger Frame Aluminum Magazine Style Fore-Grip Standard Picatinny Rail (for Mounting Scopes or Sights) Removable Composite Shoulder Stock Durable Matte Anodized Finish No-Slip Rubber Grip Panels Quick Strip Delrin Bolt 12 Muzzle Break Barrel Off-Set Feed Neck Two Finger Trigger Angled Bottomline with Drop Forward Operates on CO2 or Compressed Air E-MR1 3 Modes of Operation (Semi-Auto, Full-Auto & Burst) Rate of Fire (R.O.F.) up to 15 BPS Flux Wrap-Around Grip 2-Way Adjustable Two Finger Trigger Removable Adjustable Shoulder Stock Top Cocking Delrin Bolt 12 Muzzle Break Barrel Off-Set Feed Neck Integrated Dovetail Scope Mount Drop Forward w/ Inline Screws Anti-Double Feed Ball Detent Steel Braided Hose Line Durable Matte Anodized Finish Quick Disconnect Pin One Piece Velocity Adjuster/Spring Guide Compatible with CO2 or Compressed Air MR1 Sniper Military/ Sniper Style Sem